UNDERWRITING AGREEMENT

Exhibit 10.2

EXECUTION COPY

TIME WARNER TELECOM INC.

2.375% CONVERTIBLE SENIOR DEBENTURES DUE 2026

UNDERWRITING AGREEMENT

March 23, 2006

March 23, 2006

Morgan Stanley & Co. Incorporated

Wachovia Capital Markets, LLC

Deutsche Bank Securities Inc.

1585 Broadway

New York, NY 10036

Ladies and Gentlemen:

Time Warner Telecom Inc., a Delaware corporation (the “ Company ”), proposes to issue and sell to the several underwriters named in Schedule II hereto (the “ Underwriters ”), $325 million principal amount of its 2.375% convertible senior debentures due 2026 (the “ Firm Securities ”) to be issued pursuant to the provisions of an indenture and a supplemental indenture (each to be dated as of March 29, 2006, together, the “ Indenture ”) between the Company and Wells Fargo Bank, National Association, as Trustee (the “ Trustee ”). The Company also proposes to issue and sell to the several Underwriters not more than an additional $48.75 million principal amount of its 2.375% convertible senior debentures due 2026 (the “ Additional Securities ”) if and to the extent that Morgan Stanley & Co. Incorporated shall have determined to exercise, on behalf of the Underwriters, the right to purchase such Additional Securities (or any portion thereof) granted in Section 2 hereof. The Firm Securities and the Additional Securities are hereinafter collectively referred to as the “ Securities .” The Securities will be convertible into shares of class A common stock of the Company, par value $.01 per share (the “ Class A Common Stock ”). The shares of Class A Common Stock into which the Securities are convertible are hereinafter collectively referred to as the “ Underlying Securities .”

The Company has filed with the Securities and Exchange Commission (the “ Commission ”) a registration statement, including a prospectus, (the file number of which is set forth in Schedule I hereto) on Form S-3, relating to securities (the “ Shelf Securities ”), including the Securities, for registration under the Securities Act of 1933, as amended (the “ Securities Act ”), of such Shelf Securities and the offering thereof from time to time in accordance with Rule 415. The registration statement as amended to the date of this Agreement, including the information (if any) deemed to be part of the registration statement at the time of effectiveness pursuant to Rule 430A or Rule 430B under the Securities Act, is hereinafter referred to as the “ Registration Statement, ” and the related prospectus covering the Shelf Securities dated March 17, 2006 in the form first used to confirm sales of the Securities (or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Basic Prospectus .” The Basic Prospectus, as supplemented by the prospectus supplement specifically relating to the Securities in the form first used to confirm sales of the Securities

(or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act), is hereinafter referred to as the “ Prospectus ,” and the term “ preliminary prospectus ” means the Basic Prospectus as supplemented by the preliminary prospectus supplement dated March 17, 2006. For purposes of this Agreement, “ free writing prospectus ” has the meaning set forth in Rule 405 under the Securities Act, “ Time of Sale Prospectus ” means the preliminary prospectus together with the free writing prospectuses, if any, each identified in Schedule I hereto, and “ broadly available road show ” means a “bona fide electronic road show” as defined in Rule 433(h)(5) under the Securities Act that has been made available without restriction to any person. As used herein, the terms “Registration Statement,” “Basic Prospectus,” “preliminary prospectus,” “Time of Sale Prospectus” and Prospectus shall include the documents, if any, incorporated by reference therein. The terms “ supplement ,” “ amendment ,” and “ amend ” as used herein with respect to the Registration Statement, the Basic Prospectus, the Time of Sale Prospectus, any preliminary prospectus or free writing prospectus shall include all documents subsequently filed by the Company with the Commission pursuant to the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), that are deemed to be incorporated by reference therein.

1. Representations and Warranties . The Company represents and warrants to and agrees with each of the Underwriters that:

(a) The Registration Statement has become effective; no stop order suspending the effectiveness of the Registration Statement is in effect, and no proceedings for such purpose are pending before or, to the knowledge of the Company, threatened by the Commission. If the Registration Statement is an automatic shelf registration statement as defined in Rule 405 under the Securities Act, the Company is a well-known seasoned issuer (as defined in Rule 405 under the Securities Act) eligible to use the Registration Statement as an automatic shelf registration statement and the Company has not received notice that the Commission objects to the use of the Registration Statement as an automatic shelf registration statement.

(b) (i) Each document, if any, filed or to be filed pursuant to the Exchange Act and incorporated by reference in the Time of Sale Prospectus or the Prospectus complied or will comply when so filed in all material respects with the Exchange Act and the applicable rules and regulations of the Commission thereunder, (ii) each part of the Registration Statement, when such part became effective, did not contain, and each such part, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iii) the Registration Statement as of the date hereof does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iv) the Registration Statement and the Prospectus comply, and as amended or supplemented, if applicable, will comply in all material respects with

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the Securities Act and the applicable rules and regulations of the Commission thereunder, (v) the Time of Sale Prospectus does not, and at the time of each sale of the Securities in connection with the offering when the Prospectus is not yet available to prospective purchasers and at the Closing Date (as defined in Section 4), the Time of Sale Prospectus will not, contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, (vi) each broadly available road show, if any, when considered together with the Time of Sale Prospectus, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading and (vii) the Prospectus does not contain and, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that the representations and warranties set forth in this paragraph do not apply to (A) statements or omissions in the Registration Statement, the Time of Sale Prospectus or the Prospectus based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Underwriters expressly for use therein or (B) that part of the Registration Statement that constitutes the Statement of Eligibility (Form T-1) under the Trust Indenture Act of 1939, as amended (the “ Trust Indenture Act ”), of the Trustee.

(c) The Company is not an “ineligible issuer” in connection with the offering pursuant to Rules 164, 405 and 433 under the Securities Act. Any free writing prospectus that the Company is required to file pursuant to Rule 433(d) under the Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Each free writing prospectus that the Company has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or that was prepared by or behalf of or used or referred to by the Company complies or will comply in all material respects with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Except for the free writing prospectuses, if any, identified in Schedule I hereto, and electronic road shows each furnished to the Underwriters before first use, the Company has not prepared, used or referred to, and will not, without your prior consent, prepare, use or refer to, any free writing prospectus.

(d) The Company has been duly incorporated, is validly existing as a corporation in good standing under the laws of the State of Delaware, has the corporate power and authority to own its property and to conduct its business as described in the Time of Sale Prospectus and is duly qualified to transact business and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property requires such qualification, except to the extent that the failure to be so qualified or be in good standing would not have a material adverse effect on the Company and its subsidiaries, taken as a whole. For

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the purposes of this Agreement, the term “subsidiary” refers to all direct and indirect subsidiaries of the Company.

(e) Each subsidiary of the Company has been duly incorporated or, in the case of partnerships or limited liability companies, duly organized, is validly existing as a corporation, a partnership or a limited liability company, as the case may be, in good standing under the laws of the jurisdiction of its incorporation or organization, has the corporate power or power as a partnership or limited liability company, as applicable, and authority to own its property and to conduct its business as described in the Time of Sale Prospectus and is duly qualified to transact business and is in good standing in each jurisdiction in which the conduct of its business or its ownership or leasing of property requires such qualification, except to the extent that the failure to be so qualified or be in good standing would not have a material adverse effect on the Company and its subsidiaries, taken as a whole; all of the issued shares of capital stock of each subsidiary of the Company that is a corporation have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of any security interest, mortgage, pledge, lien, encumbrance or claim (collectively, “ Liens ”) except for any Liens securing indebtedness of the Company or its subsidiaries for borrowed money (including pursuant to its credit agreement or indentures) or as described in the Time of Sale Prospectus or Registration Statement and all of the partnership interests or limited liability company membership interests in each of the Company’s subsidiaries that is a partnership or a limited liability company, as the case may be, are owned directly or indirectly by the Company, free and clear of all Liens except for any Liens securing indebtedness of the Company or its subsidiaries for borrowed money (including pursuant to its credit agreement or indentures) or as described in the Time of Sale Prospectus or Registration Statement .

(f) This Agreement has been duly authorized, executed and delivered by the Company.

(g) The authorized capital stock of the Company conforms as to legal matters in all material respects to the description thereof contained in the Prospectus.

(h) The shares of capital stock of the Company outstanding prior to the issuance of the Securities have been duly authorized and are validly issued, fully paid and non-assessable.

(i) The Underlying Securities issuable upon conversion of the Securities have been duly authorized and reserved and, when issued upon conversion of the Securities in accordance with the terms of the Securities, will be validly issued, fully paid and non-assessable, and the issuance of the Underlying Securities will not be subject to any preemptive or similar rights.

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(j) The Indenture has been duly authorized and, when executed and delivered by the Trustee and the Company, will be a valid and binding agreement of the Company, enforceable in accordance with its terms, subject to applicable bankruptcy, insolvency or similar laws affecting creditors’ rights generally and general principles of equity.

(k) The Securities have been duly authorized and, when executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters in accordance with the terms of this Agreement will be valid and binding obligations of the Company, enforceable in accordance with their terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and general principles of equity, and will be entitled to the benefits of the Indenture.

(l) The execution and delivery by the Company of, and the performance by the Company of its obligations under, this Agreement, the Indenture and the Securities and will not contravene any provision of applicable law or the certificate of incorporation or by-laws of the Company or any of its subsidiaries or any agreement or other instrument binding upon the Company or any of its subsidiaries that is material to the Company and its subsidiaries, taken as a whole (including, without limitation, all agreements and indentures listed as Exhibits to the Company’s Annual Report on Form 10-K for its fiscal year ended December 31, 2005), or any judgment, order or decree of any governmental body, agency or court having jurisdiction over the Company or any of its subsidiaries, and no consent, approval, authorization or order of, or qualification with, any governmental body or agency is required for the performance by the Company of its obligations under this Agreement, the Indenture and the Securities, except such as have been obtained under the Securities Act and the Exchange Act and as set forth in the Time of Sale Prospectus or such as may be required by the securities or Blue Sky laws of the various states in connection with the offer and sale of the Securities.

(m) There has not occurred any material adverse change, or any development involving a prospective material adverse change, in the condition, financial or otherwise, or in the earnings, business or operations of the Company and its subsidiaries, taken as a whole, from that set forth in the Time of Sale Prospectus.

(n) There are no legal or governmental proceedings pending or, to the knowledge of the Company, threatened to which the Company or any of its subsidiaries is a party or to which any of the properties of the Company or any of its subsidiaries is subject (i) other than proceedings accurately described in all material respects in the Time of Sale Prospectus and proceedings that would not have a material adverse effect on the Company and its subsidiaries, taken as a whole, or on the power or ability of the Company to perform its obligations under this Agreement, the Indenture or the Securities or to consummate the transactions contemplated by the Prospectus or (ii) that are required to be described in the

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Registration Statement or the Prospectus and are not so described; and there are no statutes, regulations, contracts or other documents that are required to be described in the Registration Statement or the Prospectus or to be filed as exhibits to the Registration Statement that are not described or filed as required.

(o) The Company is not, and after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Prospectus will not be, required to register as an “investment company” as such term is defined in the Investment Company Act of 1940, as amended.

(p) The Company and its subsidiaries (i) are in compliance with any and all applicable foreign, federal, state and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (“ Environmental Laws ”), (ii) have received all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses and (iii) are in compliance with all terms and conditions of any such permit, license or approval, except where such noncompliance with Environmental Laws, failure to receive required permits, licenses or other approvals or failure to comply with the terms and conditions of such permits, licenses or approvals would not, singly or in the aggregate, have a material adverse effect on the Company and its subsidiaries, taken as a whole.

(q) There are no costs or liabilities associated with Environmental Laws (including, without limitation, any capital or operating expenditures required for clean-up, closure of properties or compliance with Environmental Laws or any permit, license or approval, any related constraints on operating activities and any potential liabilities to third parties) which would, singly or in the aggregate, have a material adverse effect on the Company and its subsidiaries, taken as a whole.

(r) There are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Securities Act with respect to any of the securities of the Company (except as otherwise disclosed in the Registration Statement) or to require the Company to include such securities with the Securities registered pursuant to the Registration Statement.

(s) Subsequent to the date as of which information is given in the Time of Sale Prospectus, (i) the Company has not incurred any material liability or obligation, direct or contingent, nor entered into any material transaction, in each case not in the ordinary course of business; (ii) the Company has not purchased any of its outstanding capital stock, nor declared, paid or otherwise made any dividend or distribution of any kind on its capital stock other than ordinary and customary dividends; and (iii) there has not been any material change in the capital stock, short-term debt or long-term debt of the Company and

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its subsidiaries, taken as a whole, except in each case as described in the Time of Sale Prospectus or the Registration Statement.

(t) The Company and its subsidiaries have good and marketable title in fee simple to all real property and good and marketable title to all personal property owned by them, free and clear of all Liens except for any Liens securing indebtedness of the Company or its subsidiaries for borrowed money (including pursuant to its credit agreement or indentures) or Liens permitted under its credit agreement or indentures as are described in the Time of Sale Prospectus or Registration or such as do not materially affect the value of such property and do not interfere with the use made and proposed to be made of such property by the Company and its subsidiaries; and any real property and buildings held under lease by the Company and its subsidiaries are held by them under valid, subsisting and enforceable leases with such exceptions as do not interfere with the use made and proposed to be made of such property and buildings by the Company and its subsidiaries or such as do not, singly or in the aggregate, have or could not result in a material adverse effect on the Company and its subsidiaries, taken as a whole, except in each case as described in or contemplated by the Time of Sale Prospectus.

(u) Except as described in the Time of Sale Prospectus, the Company and its subsidiaries own or possess, or can acquire on reasonable terms, all patents, patent rights, licenses, inventions, copyrights, know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), trademarks, service marks and trade names, currently employed by them in connection with the business now operated by them, except where the failure to own or possess or to have the right to acquire any of the foregoing, singly or in the aggregate, does not have a material adverse effect on the Company and its subsidiaries, taken as a whole, and neither the Company nor any of its subsidiaries has received any notice of infringement of or conflict with asserted rights of others with respect to any of the foregoing which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would have a material adverse effect on the Company and its subsidiaries, taken as a whole.

(v) Except as described in the Time of Sale Prospectus, no material labor dispute with the employees of the Company exists or, to the knowledge of the Company, is imminent, except for disputes that do not or would not have a material adverse effect on the Company and its subsidiaries, taken as a whole; and the Company is not aware, but without any independent investigation or inquiry, of any existing, threatened or imminent labor disturbance by the employees of any of its principal suppliers, manufacturers or contractors that could have a material adverse effect on the Company and its subsidiaries, taken as a whole.

(w) The Company and its subsidiaries are insured by insurers that the Company reasonably believes to be of recognized financial responsibility against such losses and risks and in such amounts as are customary in the businesses in

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which it is engaged; and neither the Company nor any of its subsidiaries has any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business at a cost that would not have a material adverse effect on the Company and its subsidiaries, taken as a whole, except as described in or contemplated by the Time of Sale Prospectus.

(x) (i) The Company and its subsidiaries possess all permits, licenses, rights of way, approvals, consents and other authorizations (collectively issued by the appropriate federal, state or local regulatory agencies or bodies, (including the Federal Communications Commission (the “ FCC ”), the public utilities commission, or any equivalent body, of each state in which the Company and its subsidiaries do business and any other relevant state or local governmental department, commission, board, bureau, agency, court or other authority thereof (the “ Local Authorities ”)) required for the conduct of the telecommunications business now operated by the Company and its subsidiaries (collectively, the “ Governmental Licenses ”), except where the failure to possess any such Governmental Licenses would not, singly or in the aggregate, have a material adverse effect on the Company and its subsidiaries, taken as a whole; the Company and its subsidiaries are in compliance with the terms and conditions of all such Governmental Licenses, except where the failure so to comply would not, singly or in the aggregate, have a material adverse effect on the Company and its subsidiaries, taken as a whole; all of the Governmental Licenses are valid and in full force, except where the invalidity of such Governmental Licenses or the failure of such Governmental Licenses to be in full force and effect would not, singly or in the aggregate, have a material adverse effect on the Company and its subsidiaries, taken as a whole; there is no outstanding adverse judgment, decree or order that has been issued by the FCC or any of the Local Authorities against the Company or any of its subsidiaries and which, singly or in the aggregate, would have a material adverse effect of the Company and its subsidiaries, taken as a whole; and neither the Company nor any of its subsidiaries has received any notice of or is not aware of proceedings relating to the revocation or modification of any such Governmental Licenses or, except as set forth in the Time of Sale Prospectus, that would otherwise affect the operations of the Company or its subsidiaries and which, singly or in the aggregate, would have a material adverse effect on the Company and its subsidiaries, taken as a whole.

(y) There is, and has been, no failure on the part of the Company or its subsidiaries, or any of their directors or officers, in their capacities as such, to comply in all material respects with any provision of the Sarbanes Oxley Act of 2002 and the rules and regulations promulgated in connection therewith including, without limitation, Section 402 related to loans and Sections 302 and 906 related to certifications.

(z) The Company maintains a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations, (ii) transactions

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are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability and (iii) access to assets is permitted only in accordance with management’s general or specific authorization, and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences.

(aa) Ernst & Young LLP, who reported on the annual consolidated financial statements of the Company incorporated by reference in the Registration Statement and the Prospectus, are independent accountants as required by the Securities Act.

2. Agreements to Sell and Purchase . The Company hereby agrees to sell to the several Underwriters, and each Underwriter, upon the basis of the representations and warranties herein contained, but subject to the conditions hereinafter stated, agrees, severally and not jointly, to purchase from the Company the respective principal amounts of Firm Securities set forth in Schedule II hereto opposite its name at the purchase price set forth in Schedule I hereto.

On the basis of the representations and warranties contained in this Agreement, and subject to its terms and conditions, the Company agrees to issue and sell to the Underwriters the Additional Securities, and the Underwriters shall have the right to purchase, severally and not jointly, up to $48.75 million principal amount of Additional Securities at the Purchase Price plus accrued interest, if any, to the date of payment and delivery. The Underwriters may exercise these rights in whole or from time to time in part by giving written notice of each election to exercise the foregoing option not later than 30 days after the date of this Agreement. Any exercise notice shall specify the principal amount of Additional Securities to be purchased by the Underwriters and the date on which such Additional Securities are to be purchased. Each purchase date must be at least one business day after the written notice is given and may not be earlier than the Closing Date for the Firm Securities nor later than ten business days after the date of such notice. Additional Securities may be purchased as provided in Section 3 hereof solely for the purpose of covering over allotments made in connection with the offering of the Firm Securities. On each day, if any, that Additional Securities are to be purchased (each an “ Option Closing Date ”), each Underwriter agrees, severally and not jointly, to purchase the principal amount of Additional Securities (subject to such adjustments to eliminate fractional securities as you may determine) that bears the same proportion to the total number of Additional Securities to be purchased on such Option Closing Date as the principal amount of Firm Securities set forth in Schedule II hereto opposite the name of such Underwriter bears to the total principal amount of Firm Securities.

The Company hereby agrees that, without the written consent of Morgan Stanley & Co. Incorporated, Wachovia Capital Markets, LLC and Deutsche Bank Securities Inc. on behalf of the Underwriters, it will not, during the period ending

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90 days after the date of the Prospectus, (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Class A Common Stock or any securities convertible into or exercisable or exchangeable for Class A Common Stock, (ii) file any registration statement with the Commission relating to the offering of any shares of Class A Common Stock or (iii) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Class A Common Stock, whether any such transaction described in clause (i), (ii) or (iii) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise.

The foregoing paragraph shall not apply to (i) the Securities to be sold hereunder or the Underlying Securities, (ii) the issuance by the Company of shares of Common Stock upon the exercise of an option or warrant or the conversion of a security outstanding on the date hereof and as described in the Prospectus (or filing a registration statement with the Commission related to the issuance or resale of such Class A Common Stock), (iii) the issuance by the Company of any shares of Common Stock, options or other securities to or for the benefit of employees of the Company on or after the date hereof pursuant to the Company’s employee stock ownership plan or equity incentive plans as described in the Time of Sale Prospectus or the Registration Statement and the issuance by the Company of shares of Class A Common Stock upon the exercise of any such options or other securities (or filing a registration statement with the Commission related to the issuance or resale of such Class A Common Stock).

If:

(1) during the last 17 days of the 90-day restricted period described in the third paragraph of this Section 2, the Company issues an earnings release or material news or a material event relating to the Company occurs; or

(2) prior to the expiration of the 90-day restricted period described in the third paragraph of this Section 2, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the restricted period; and in each case

(3) at the end of the 90-day restricted period described in the third paragraph of this Section 2, (i) the Company’s shares are not “actively traded securities” as such term is defined in Regulation M under the Securities Act or (ii) the Underwriters are not able to publish or distribute research reports concerning the Company or its industry pursuant to Rule 139 of the Securities Act,

then the restrictions imposed by this Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

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3. Public Offering . The Company is advised by the Underwriters that they propose to make a public offering of their respective portions of the Securities as soon after this Agreement has been executed as in your judgment is advisable. The Company is further advised by the Underwriters that the Securities are to be offered to the public upon the terms set forth in the Prospectus.

4. Payment and Delivery . Payment for the Firm Securities shall be made to the Company in Federal or other funds immediately available in New York City on the closing date and time set forth in Schedule I hereto, or at such other time on the same or such other date, not later than the fifth business day thereafter, as may be designated by Morgan Stanley & Co. Incorporated in writing. The time and date of such payment are hereinafter referred to as the “ Closing Date .”

Payment for the Firm Securities shall be made against delivery to Morgan Stanley & Co. Incorporated on the Closing Date for the respective accounts of the several Underwriters of the Firm Securities registered in such names and in such denominations as Morgan Stanley & Co. Incorporated shall request in writing not less than one full business day prior to the Closing Date, with any transfer taxes payable in connection with the transfer of the Firm Securities to the Underwriters duly paid.

Payment for any Additional Securities shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Additional Securities for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on the date specified in the corresponding notice described in Section 2 or at such other time on the same or on such other date, in any event not later than May 8, 2006, as shall be designated in writing by you.

Payment for the Additional Securities shall be made against delivery to Morgan Stanley & Co. Incorporated on the Option Closing Date for the respective accounts of the several Underwriters of the Additional Securities registered in such names and in such denominations as you shall request in writing not less than one full business day prior to the relevant Option Closing Date, with any transfer taxes payable in connection with the transfer of the Additional Securities to the Underwriters duly paid set forth on Schedule I hereto.

The Firm Securities and Additional Securities shall be in definitive form or global form, as specified by Morgan Stanley & Co. Incorporated, and in such denominations as Morgan Stanley & Co. Incorporated shall request in writing not later than one full business day prior to the Closing Date or the applicable Option Closing Date, as the case may be. The Firm Securities and Additional Securities shall be delivered to Morgan Stanley & Co. Incorporated on the Closing Date for the respective accounts of the several Underwriters, with any transfer taxes

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payable in connection with the transfer of the Securities to the Underwriter duly paid, against payment of the Purchase Price therefor.

5. Conditions to the Underwriters’ Obligations . The several obligations of the Underwriters are subject to the following conditions:

(a) Subsequent to the execution and delivery of this Agreement and prior to the Closing Date:

(i) there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any review for a possible change that does not indicate the direction of the possible change, in the rating accorded the Company or any of the securities of the Company or any of its subsidiaries or in the rating outlook for the Company by any “nationally recognized statistical rating organization,” as such term is defined for purposes of Rule 436(g)(2) under the Securities Act; and

(ii) there shall not have occurred any change, or any development involving a prospective change, in the condition, financial or otherwise, or in the earnings, business or operations of the Company and its subsidiaries, taken as a whole, from that set forth in the Time of Sale Prospectus that, in your judgment, is material and adverse and that makes it, in your judgment, impracticable to market the Securities on the terms and in the manner contemplated in the Time of Sale Prospectus.

(b) The Underwriters shall have received on the Closing Date a certificate, dated the Closing Date and signed by an executive officer of the Company, to the effect set forth in Section 5(a)(i) above and to the effect that the representations and warranties of the Company contained in this Agreement are true and correct in all material respects as of the Closing Date and that the Company has complied in all material respects with all of the agreements and satisfied all of the conditions on its part to be performed or satisfied hereunder on or before the Closing Date.

The officer signing and delivering such certificate may rely upon the best of his or her knowledge as to proceedings threatened.

(c) The Underwriters shall have received on the Closing Date an opinion of Faegre & Benson LLP, outside counsel for the Company, dated the Closing Date, to the effect that:

(i) to such counsel’s knowledge, (A) there are not any pending or threatened governmental proceedings before any court or governmental agency or authority or any arbitrator to which the Company is a party or to which any of the properties of the Company is subject of a character required to be disclosed in the Time of Sale Prospectus which are not disclosed as required, and (B) there is no contract, indenture, mortgage,

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loan agreement, note, lease or other document of a character required to be described in the Time of Sale Prospectus which is not described as required;

(ii) the shares of capital stock of the Company outstanding prior to the issuance of the Securities have been duly authorized and are validly issued and fully paid and non-assessable;

(iii) the Securities conform in all material respects to the description thereof contained in the Time of Sale Prospectus;

(iv) the Securities have been duly authorized and, when executed and authenticated in accordance with the provisions of the Indenture and delivered to and paid for by the Underwriters in accordance with the terms of this Agreement, will be valid and binding obligations of the Company, enforceable in accordance with their terms, subject to the effects of applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and equitable principles of general applicability, and will be entitled to the benefits of the Indenture;

(v) the Underlying Securities issuable upon conversion of the Securities have been duly authorized and reserved and, when issued upon conversion of the Securities in accordance with the terms of the Securities, will be validly issued, fully paid and non-assessable, and the issuance of the Underlying Securities will not be subject to any preemptive or similar rights under (A) the Delaware General Corporation Law, (B) the certificate of incorporation or by-laws of the Company, or (C) to the knowledge of such counsel, any agreement or instrument to which the Company is a party;

(vi) this Agreement has been duly authorized, executed and delivered by the Company;

(vii) the Indenture has been duly qualified under the Trust Indenture Act and has been duly authorized, executed and delivered by, and is a valid and binding agreement of, the Company, enforceable in accordance with its terms, subject to applicable bankruptcy, insolvency and similar laws affecting creditors’ rights generally and equitable principles of general applicability;

(viii) the execution and delivery by the Company of, and the performance by the Company of its obligations under, this Agreement, the Indenture and the Securities will not contravene any provision of applicable law or the certificate of inco