AGREEMENT FOR JMG OIL & GAS, LP an Oklahoma Limited Partnership Dated January 28, 2005

Exhibit 3.25

AGREEMENT FOR JMG OIL & GAS, LP

an Oklahoma Limited Partnership

Dated January 28, 2005

TABLE OF CONTENTS

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AGREEMENT FOR JMG OIL & GAS LP

THIS LIMITED PARTNERSHIP AGREEMENT (“Agreement”) is made and entered into on the 28th day of January, 2005, by and between J. M. Graves, L.L.C., an Oklahoma Limited Liability Company, successor to Paul Korte, the original General Partner, (the “General Partner”) and those persons who execute this Agreement as limited partners (hereinafter referred to collectively, whether one or more, as the “Limited Partners”) (the General Partner and the Limited Partners being sometimes hereinafter collectively called the “Partners” and sometimes individually a “Partner”).

PURPOSE OF THE PARTNERSHIP

The purpose of this Partnership is to accomplish the following:

In recognition of the foregoing and in consideration of the mutual covenants contained herein, the Partners hereby agree as follows:

ARTICLE I

ORGANIZATION

Section 1.1. Formation . The Partners hereby form a limited partnership (the “Partnership”) under the provisions of Okla. Stat. Ann. tit . 54, §§ 301-365 (the “Act”) on the terms and conditions hereinafter set forth, and agree to conduct such business under the name and style of “JMG Oil & Gas, LP.”

Section 1.2. Certificate of Limited Partnership . The General Partner has executed a Certificate of Limited Partnership and has caused the same to be filed as required in accordance with the laws of the state of Oklahoma.

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ARTICLE II

CHARACTER, PLACE OF BUSINESS AND TERM OF PARTNERSHIP

Section 2.1. Character of Business . The Partnership has been organized to carry on any business that a partnership without limited partners may carry on, except to carry on business as a bank or domestic insurer. To consummate the foregoing and to carry out the obligations of the Partnership in connection therewith or incidental thereto and to further the Purpose of the Partnership, the General Partner shall have the authority, in accordance with and subject to the limitations set forth in Article V hereof, to cause the Partnership: to borrow money and to make and issue notes, obligations and evidences of indebtedness of all kinds, whether secured by mortgage, pledge or otherwise, and to secure the same by mortgage, pledge or otherwise; to make, enter into, perform and carry out any arrangements, contracts and/or agreements of every kind for any lawful purpose without limit as to amount or otherwise, with any corporation, association, partnership, firm, trustee, syndicate, individual and/or any political or governmental division or subdivision, domestic or foreign; and generally to make and perform agreements and contracts of every kind and description and to do any and all things necessary or incidental to the foregoing for the protection and enhancement of the assets of the Partnership.

Section 2.2. Place of Business . The principal office of the Partnership shall be located at 2455 East 51 ^st Street, Tulsa, Oklahoma 74105, or such other place as the General Partner may from time to time determine. The Partnership may also maintain such other offices at such other places as the General Partner may from time to time determine.

Section 2.3. Term . The Partnership shall commence on the date that the Certificate of Limited Partnership is duly filed as required by Oklahoma law and shall continue in perpetuity unless it is earlier dissolved or terminated pursuant to law or the provisions of this Agreement.

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ARTICLE III

CAPITAL CONTRIBUTIONS

Section 3.1. General Partner . The General Partner has contributed or will contribute capital to the Partnership as more fully set forth in Exhibit “A”, valued as set forth therein.

Section 3.2. Limited Partners . The Limited Partners have contributed or will contribute capital to the Partnership as more fully set forth in Exhibit “A,” valued as set forth therein.

Section 3.3. Interest . No interest shall be paid by the Partnership on the capital contributions of any Partner.

Section 3.4. Units . The Partnership shall issue Units representing a Partner’s interest in the Partnership. One Unit shall be issued for each One Dollar ($1.00) of cash, property or note or other obligation to contribute cash or property to the Capital of the Partnership a partner so contributes to the Partnership. Each Unit shall have one vote on each matter brought before the Partnership.

Section 3.5. Scope of Limited Partner Liability . Except as otherwise provided by this Agreement, the Limited Partners shall not be liable for the debts, liabilities, contracts or other obligations of the Partnership. Except as otherwise provided by this Agreement, or applicable state Law, a Limited Partner shall be liable only to make the capital contribution described herein and shall not be required to lend any funds to the Partnership or, after the required capital contribution has been made, to make any additional contributions to the Partnership.

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ARTICLE IV

PROFITS, LOSSES AND ACCOUNTING

Section 4.1. Allocation of Profits and Losses .

(a) Except as otherwise provided herein, all items of income, gain, loss, deduction or credit of the Partnership shall be allocated between or borne by the Partners in accordance with their respective Units in the partnership.

(b) Notwithstanding any provision of this Agreement to the contrary, to the extent required by law, income, gain, loss, and deduction attributable to property contributed to the Partnership by a Partner shall be allocated between the Partners so as to take into account any variation between the tax basis of the property and the fair market value thereof at the time of contribution, in accordance with the requirements of Section 704 ^© ) of the Internal Revenue Code of 1986 (the “Code”), or its counterpart in any subsequently enacted Internal Revenue Code, and the applicable Treasury Regulations (the “Regulations”) thereunder, as more fully described in Exhibit “B” hereto.

(c) Partnership profits, losses and gains shall be allocated among the Partners in accordance with the portion of the year during which the Partners have held their respective Units. All items of income and loss shall be considered to have been earned ratably over the fiscal year of the Partnership, except that gains and losses arising from the disposition of assets shall be taken into account as of the date thereof.

(d) Notwithstanding any provision of this Agreement to the contrary, in the event the Partnership is entitled to a deduction for imputed interest under any provision of the Code on any loan or advance from a Partner, such deduction shall be allocated solely to such Partner.

(e) Notwithstanding any provision of this Agreement to the contrary, if there is a net decrease in Partnership Minimum Gain during any Partnership fiscal year, Partners who would

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otherwise have an Adjusted Deficit Capital Account Balance at the end of such year shall be specially allocated items of Partnership income and gain for such year (and, if necessary, subsequent years) in an amount and manner sufficient to eliminate such Adjusted Deficit Account Balance as quickly as possible. The items to be so allocated shall be determined in accordance with Section 1.704-2(f) of the Regulations. “Partnership Minimum Gain” shall have the same meaning as is ascribed thereto in Section 1.704-2(g) of the Regulations. “Adjusted Deficit Capital Account Balance” shall mean the deficit balance of a Partner’s capital account in excess of the amount of the deficit, if any, the Partner is obligated to contribute to the Partnership under this Agreement or is deemed obligated to restore pursuant to the Regulations under Code Section 704(b).

(f) Notwithstanding any provision of this Agreement to the contrary, to the extent the payment of any expenditure by the Partnership is treated as a distribution to a Partner for federal income tax purposes, there shall be a gross income allocation to such Partner in the amount of such distribution.

(g) Notwithstanding any provision of this Agreement to the contrary, if items of income or gain to be allocated include income or gain treated as ordinary income for federal income tax purposes because it is attributable to the recapture of depreciation under Section 1245 or 1250 of the Code, such income or gain, to the extent treated as ordinary income, shall be allocated to and reported by the Partners in proportion to their then respective cumulative allocations of depreciation.

(h) Notwithstanding any provision of this Agreement to the contrary, except as provided in subsection 4.1(f) hereof, in the event any Partner unexpectedly receives any adjustments, allocations, or distributions described in Sections 1.704-1(b)(2)(ii)(d)(4), (5) or (6)

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of the Regulations, items of Partnership income and gain shall be specially allocated to such Partner in an amount and manner sufficient to eliminate as quickly as possible the Adjusted Deficit Capital Account Balance in the Partner’s capital account created by such adjustments, allocations, or distributions. Any special allocations of items of income or gain pursuant to this subsection 4.1(h) shall be taken into account in computing subsequent allocations of other net profits, net losses and items thereof pursuant to this Section 4.1, so that the net amount of any items so specially allocated pursuant to this subsection 4.1(h) and the other net profits, net losses and all other items allocated to the Partner pursuant to this Section 4.1 shall, to the extent possible, be equal to the net amount that would have been allocated to the Partner pursuant to the provisions of this Section 4.1 had such unexpected adjustments, allocations or distributions not occurred.

(i) Except as provided in subsection 4.1(f) above, in the event any Limited Partner has an Adjusted Deficit Capital Account Balance at the end of any Partnership fiscal year which is in excess of the sum of (i) the amount the Limited Partner is obligated to restore pursuant to any provision of this Agreement, and (ii) the amount the Limited Partner is deemed to be obligated to restore pursuant to the penultimate sentence of Section 1.704-1(b)(4)(iv)(f) of the Regulations, such Limited Partner shall be specially allocated items of Partnership income and gain in the amount of such excess as quickly as possible.

Section 4.2. Accounting .

(a) The Partnership books shall be kept on the accrual basis and in accordance with reasonable accounting principles consistently applied.

(b) The fiscal year of the Partnership shall end on December 31.

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(c) The terms “net profits” and “net losses,” as used herein, shall mean the net amount of the Partnership’s profits and losses, as determined for federal income tax purposes, and shall also include each Partner’s share of income described in Section 705(a)(1)(B) of the Code, any expenditures described in Section 705(a)(2)(B) of the Code, any expenditures described in Section 709(a) of the Code which are not deducted or amortized in accordance with Section 709(b) of the Code, basis adjustments required pursuant to Section 48(q) of the Code and losses not deductible pursuant to Section 267(a) or 707(b) of the Code.

Section 4.3. Partner’s Capital Accounts .

(a) There shall be maintained a capital account for each Partner in accordance with this Section 4.3 and the principles set forth in Exhibit “C” hereto. The amount of each Partner’s contribution of cash and property to the capital of the Partnership shall be credited to such Partner’s capital account, and from time to time, but not less often than quarterly, the share of each Partner in profits, losses and distributions shall be credited or charged, as the case may be, to such Partner’s capital account. The determination of a Partner’s capital account, and any adjustments thereto, shall be made consistently with tax accounting and other principles set forth in Section 704(b) of the Code and applicable Regulations thereunder.

(b) If, at any time, the Partnership shall suffer a loss as a result of which the capital account of any Partner shall be a negative amount, such loss shall be carried as a charge against that Partner’s capital account, and that Partner’s share of subsequent profits of the Partnership shall be applied to restore such capital account deficit.

(c) Immediately following the transfer of any Unit, the capital account of the transferee Partner shall be equal to the capital account of the transferor Partner attributable to the transferred Unit.

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(d) For purposes of computing the amount of any item of income, gain, deduction or loss to be reflected in the Partners’ capital accounts, the determination, recognition and classification of any such item shall be the same as its determination, recognition and classification for federal income tax purposes, taking into account any adjustments required pursuant to Section 704(b) of the Code and the applicable Regulations thereunder, as more fully described in Exhibit “C” hereof.

ARTICLE V

POWERS, DUTIES, LIABILITIES, AND COMPENSATION OF GENERAL PARTNER

Section 5.1. Powers of General Partner . The General Partner shall manage or cause to be managed, and shall have ultimate control of, the business and affairs of the Partnership and shall make all decisions affecting the business and assets of the Partnership and, without limitation, shall have the power to:

(a) authorize or approve all actions with respect to: (i) distributions out of the Partnership; (ii) the acquisition, encumbering or disposition of properties or leases; and (iii) the borrowing of funds and the execution of contracts, bonds, guarantees, notes, mortgages and all other instruments to effect the purposes of this Agreement; provided, however, that: (1) the consent of Limited Partners owning a majority of the Units in the Partnership shall be required before the Partnership may (A) enter into a binding agreement for the sale, exchange, leasing (other than in the ordinary course of the Partnership’s business) or other disposition of substantially all of the assets of the Partnership, (B) bring about the dissolution and winding up of the limited partnership or continuation of the business of the limited partnership upon the occurrence of any event which otherwise requires the winding up and termination of its affairs, (C) bring about the admission or removal of a general partner, or (D) make an amendment to the

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partnership agreement or certificate of limited partnership; and (2) cash distributions shall be governed by the provisions of Article VII hereof; and

(b) employ such persons, firms or corporations for the conduct of the business of the Partnership to act in such capacities and with such titles as shall be deemed by the General Partner to be necessary or desirable, including, but not limited to, contractors, accountants and attorneys, on such terms and for such reasonable compensation as is paid in the Tulsa, Oklahoma area, notwithstanding the fact that any Partner may have a financial interest in such entities.

The General Partner also shall possess those additional powers specifically designated in this Agreement, under law, and powers delegated to it from time to time by the Limited Partners.

Section 5.2. Duties of General Partner .

(a) The General Partner, subject to the limitations contained in Section 5.1 hereof, shall manage or cause to be managed the affairs of the Partnership in a prudent and businesslike manner and shall devote such part of its time, effort and personnel to the Partnership affairs as is reasonably necessary for the conduct of such affairs.

(b) In carrying out its obligations, the General Partner shall:

(i) render periodic reports to all Partners with respect to the operations of the Partnership on at least an annual basis;

(ii) on or before March 15th of every year, mail to all persons who were Partners at any time during the Partnership’s prior fiscal year an annual certified report of the Partnership, including all necessary tax information, a report of a firm of certified public accountants containing reviewed financial statements, and any other information regarding the Partnership and its operations during the prior fiscal year deemed by the General Partner to be material;

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(iii) obtain and maintain such casualty insurance and such public liability and other insurance as may be available and it deems necessary or appropriate;

(iv) deposit all funds of the Partnership in one or more separate bank accounts in the name of the Partnership with such banks or trust companies as it may designate (withdrawals from such bank accounts to be made upon the signature of such persons as shall be designated by the General Partner);

(v) maintain complete and accurate records of all properties owned or leased by the Partnership and complete and accurate books of account (containing such information as shall be necessary to record allocations and distributions), and make such records and books of account available for inspection and audit by any Partner or such Partner’s duly authorized representative (at the expense of such Partner) during regular business hours and at the principal office of the Partnership; and

(vi) cause to be filed such certificates and do such other acts as may be required by law to qualify and maintain the Partnership as a limited partnership formed under the laws of the state of Oklahoma and doing business in the appropriate states, copies of which certificates shall be filed with the records of the Partnership.

Section 5.3. Liabilities of General Partner . In carrying out its duties hereunder, the General Partner shall not be liable to the Partnership or to any other Partner for any actions taken in good faith and reasonably believed to be in the best interests of the Partnership, or for errors of judgment, but the General Partner shall be liable for willful misconduct, breach of the General Partner’s fiduciary duties or breach of this Agreement.

Section 5.4. Compensation of General Partner . The General Partner shall receive reasonable compensation for services rendered to the Partnership and shall be reimbursed for its

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expenses incurred on behalf of and for the benefit of the Partnership. Reasonable compensation shall be                                                                           .

Section 5.5. Reliance on Act of General Partner . No financial institution or any other person, firm or corporation dealing with the General Partner or the Partnership shall be required to ascertain whether the General Partner is acting in accordance with this Agreement, but such financial institution or such other person, firm or corporation shall be protected in relying solely upon the deed, transfer, or assurance of and the execution of such instrument or instruments by the General Partner.

ARTICLE VI

RIGHTS, PROHIBITIONS AND LIABILITIES OF LIMITED PARTNER

Section 6.1. Rights of the Limited Partners .

(a) The Limited Partners shall in no way be restricted or prohibited from engaging, or owning an interest, in any other business venture of any nature, including any venture which might be competitive with the business of the Partnership, and the Partnership may engage any of the Limited Partners or persons associated with a Limited Partner for specific purposes and may otherwise deal with any of the Limited Partners on terms and for compensation to be agreed upon by the Limited Partner and the Partnership; provided, however, that none of the Limited Partners shall be entitled to participate in the control of the business of the Partnership except to the extent contemplated by the Act.

(b) The Limited Partners shall be entitled to have the Partnership books, and such certificates as may be required by law to qualify and maintain the Partnership as a limited partnership under the laws of the state of Oklahoma, kept at the principal place of business of the Partnership and at all times, during reasonable business hours and at the Limited Partners’ sole expense, shall be entitled to inspect and copy any of them and have on demand true and full

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information regarding the state of the business and financial condition of the Partnership. The Limited Partners shall also be entitled to receive a copy of the Partnership’s federal, state and local income tax returns and reports for each year, promptly after such returns and reports become available, true and frill information of all other things affecting the Partnership, and a formal accounting of Partnership affairs whenever circumstances render it just and reasonable.

Section 6.2. Prohibitions with Respect to the Limited Partners . The Limited Partners shall not have the right:

(a) to take part in the control of the Partnership business or to sign for or to bind the Partnership, such power being vested solely in the General Partner;

(b) to have the Limited Partners’ capital contributions repaid except to the extent provided in this Agreement;

(c) to require partition of Partnership property or to compel any sale or appraisement of Partnership assets or sale of a deceased Partner’s interests therein; or

(d) to sell or assign a Limited Partner’s Units or to constitute the vendee or assignee thereunder a Substitute Limited Partner, except as provided in Article VIII hereof

ARTICLE VII

DISTRIBUTIONS AND PAYMENTS TO PARTNERS

Section 7.1. Distributions .

(a) The Cash Flow (as hereinafter defined) of the Partnership shall be distributed from time to time as the General Partner shall determine. Notwithstanding the foregoing, the General Partner shall distribute to the Partners all amounts of cash which the General Partner, in its sole judgment, deems necessary to allow the Partners to pay all federal and state income taxes associated with the income of the Partnership. Such distribution shall be mandatory and shall be made on or before the due date of each quarterly estimate of federal income tax. All distributions

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shall be made to the Partners pro rata, according to the number of Units held by each Partner, with all outstanding Units being treated alike. The term “Cash Flow” as used herein shall mean the gross cash revenues and funds received by the Partnership (other than funds received as capital contributions of the Partners under the terms of this Agreement), including, without limitation, net proceeds from the sale, exchange or other disposition of Partnership property, less the sum of (1) all cash expenditures made by the Partnership which the Partnership is obligated to make in the operation of or in connection with the business or any part thereof during such period, including, without limitation, payroll expenses, business taxes, real and personal property taxes, severance taxes and assessments, supplies, licenses and permit fees, repair and maintenance expenses, utility charges, insurance premiums, debt service, reasonable reserves as established by the General Partner and/or as required by any lender or any third party; and (2) expenditures by the Partnership for capital improvements, but before any deduction for depreciation or other non-cash expenses.

(b) The net proceeds of any sale or refinancing of held properties or from any other extraordinary event, such as an insured casualty or a condemnation, shall be distributed in accordance with the provisions of this Article VII.

Section 7.2. Withdrawal . No Partner shall be entitled to make withdrawals from its capital account, except to the extent of distributions made under this Article VII or Article X.

ARTICLE VIII

TRANSFERS OF UNITS

Section 8.1. General Partner . Except as otherwise provided in this Section 8.1, without the express written consent of Limited Partners owning a majority of the Units held by the Limited Partners in t