EXECUTION COPY

ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

THIS ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT (this “Assignment”), dated as of July 1, 2007, is entered into among J.P. Morgan Acceptance Corporation I, a Delaware corporation (the “Depositor”), U.S. Bank National Association, as trustee (the “Trustee”) of J.P. Morgan Mortgage Trust 2007-S3 (the “Trust”), J.P. Morgan Mortgage Acquisition Corp. (“JPMorgan Acquisition”), JPMorgan Chase Bank, National Association (“JPMCBNA”), American Home Mortgage Servicing, Inc. (“American Home Servicing”) and Wells Fargo Bank, N.A. (the “Master Servicer”).

RECITALS

WHEREAS JPMorgan Acquisition, American Home Mortgage Corp. and American Home Servicing entered into a certain Mortgage Loan Sale Agreement, dated as of April 1, 2006 (the “Purchase Agreement”) pursuant to which JPMorgan Acquisition has acquired certain mortgage loans pursuant to the terms of the Purchase Agreement;

WHEREAS JPMorgan Acquisition and American Home Servicing entered into a certain Flow Mortgage Loan Interim Servicing Agreement, dated as of April 1, 2006 (the “Interim Servicing Agreement”) pursuant to which American Home Servicing agreed to service certain mortgage loans pursuant to the terms of the Interim Servicing Agreement;

WHEREAS JPMorgan Acquisition and JPMCBNA entered into a certain Amended and Restated Flow Servicing Agreement, dated as of July 1, 2006, as amended by that certain Amendment Reg AB, dated as of January 1, 2006 (the “Servicing Agreement” and together with the Interim Servicing Agreement and the Purchase Agreement, the “Agreements”) pursuant to which JPMCBNA agreed to service certain mortgage loans pursuant to the terms of the Servicing Agreement;

WHEREAS the Depositor has agreed, on the terms and conditions contained herein, to purchase from JPMorgan Acquisition certain of the mortgage loans (the “Specified Mortgage Loans”) which are subject to the provisions of the Purchase Agreement and are listed on the mortgage loan schedule attached as Exhibit I hereto (the “Specified Mortgage Loan Schedule”);

WHEREAS American Home Servicing has agreed, on the terms and conditions contained herein, to service the Specified Mortgage Loans pursuant to the Interim Servicing Agreement and will transfer the servicing of certain mortgage loans to JPMCBNA on August 1, 2007 and September 1, 2007 (together, the “Transfer Dates”), as identified on the Specified Mortgage Loan Schedule;

WHEREAS JPMCBNA (in such capacity, the “Servicer”) has agreed, on the terms and conditions contained herein, to service the Specified Mortgage Loans pursuant to the Servicing Agreement after the applicable Transfer Dates;

WHEREAS, pursuant to the Servicing Agreement, JPMCBNA has agreed to service the Specified Mortgage Loans for a Servicing Fee Rate of 0.25%; and

WHEREAS, pursuant to the Interim Servicing Agreement, American Home Servicing has agreed to service the Specified Mortgage Loans for a Servicing Fee Rate of 0.10%; and

WHEREAS the Trustee, on behalf of the Trust, has agreed, on the terms and conditions contained herein, to purchase from the Depositor the Specified Mortgage Loans;

NOW, THEREFORE, in consideration of the mutual promises contained herein and other good and valuable consideration (the receipt and sufficiency of which are hereby acknowledged), the parties agree as follows:

1.

Assignment and Assumption

(a)

On and as of the date hereof, JPMorgan Acquisition hereby sells, assigns and transfers to the Depositor all of its right, title and interest in the Specified Mortgage Loans and all rights related thereto as provided under the Agreements to the extent relating to the Specified Mortgage Loans, the Depositor hereby accepts such assignment from JPMorgan Acquisition (the “First Assignment and Assumption”).

JPMorgan Acquisition specifically reserves and does not assign to the Depositor hereunder any and all right, title and interest in, to and under and all obligations of JPMorgan Acquisition with respect to any mortgage loans subject to the Agreements which are not the Specified Mortgage Loans.

(b)

On and as of the date hereof, immediately after giving effect to the First Assignment and Assumption, the Depositor hereby sells, assigns and transfers to the Trustee, on behalf of the Trust, all of its right, title and interest in the Specified Mortgage Loans and all rights related thereto as provided under the Agreements to the extent relating to the Specified Mortgage Loans, and the Trustee, on behalf of the Trust, hereby accepts such assignment from the Depositor (the “Second Assignment and Assumption”).

(c)

On and as of the date hereof, JPMorgan Acquisition represents and warrants to the Depositor and the Trustee that JPMorgan Acquisition has not taken any action that would serve to impair or encumber the respective ownership interests of the Depositor and the Trustee in the Specified Mortgage Loans since the date of JPMorgan Acquisition’s acquisition of the Specified Mortgage Loans.

2.

Recognition of Trustee

(a)

From and after the date hereof, JPMorgan Acquisition shall note the transfer of the Specified Mortgage Loans to the Trustee, in its books and records and shall recognize the Trustee, on behalf of the Trust, as of the date hereof, as the owner of the Specified Mortgage Loans, and American Home Servicing and the Servicer, after the applicable Transfer Dates, shall service the Specified Mortgage Loans for the benefit of the Trust pursuant to the Interim Servicing Agreement and the Servicing Agreement, as applicable, the terms of which are incorporated herein by reference. It is the intention of American Home Servicing, the Servicer, the Depositor, the Trustee and JPMorgan Acquisition that this Assignment shall be binding upon and inure to the benefit of the Depositor, the Trustee and JPMorgan Acquisition and their respective successors and assigns.

(b)

Without in any way limiting the foregoing, the parties confirm that this Assignment includes the rights relating to amendments and waivers under the Agreements.  Accordingly, the right of JPMorgan Acquisition to consent to any amendment of the Agreements and its rights concerning waivers as set forth in the applicable section of each Agreement shall be exercisable, to the extent any such amendment or waiver affects the Specified Mortgage Loans or any of the rights under the Agreements with respect thereto (including, without limitation, the servicing of the Specified Mortgage Loans), by the Trustee as assignee of JPMorgan Acquisition.

3.

Representations and Warranties

(a)

The Depositor represents and warrants that it is a sophisticated investor able to evaluate the risks and merits of the transactions contemplated hereby, and that it has not relied in connection therewith upon any statements or representations of the JPMorgan Acquisition other than those contained in the Agreements or this Assignment.

(b)

Each of the parties hereto represents and warrants that it is duly and legally authorized to enter into this Assignment.

(c)

Each of the parties hereto represents and warrants that this Assignment has been duly authorized, executed and delivered by it and (assuming due authorization, execution and delivery thereof by each of the other parties hereto) constitutes its legal, valid and binding obligation, enforceable against it in accordance with its terms, except as such enforcement may be limited by bankruptcy, insolvency, reorganization or other similar laws affecting the enforcement of creditors’ rights generally and by general equitable principles (regardless of whether such enforcement is considered in a proceeding in equity or at law).

4.

The Servicer and American Home Servicing hereby acknowledge that Wells Fargo Bank, N.A. has been appointed as the Master Servicer of the Specified Mortgage Loans pursuant to the pooling and servicing agreement dated as of the date hereof among the Depositor, the Master Servicer, the Securities Administrator and the Trustee (the “Pooling and Servicing Agreement”) for Mortgage Pass-Through Certificates, Series 2007-S3 and, therefore, has the right to enforce all obligations of American Home Servicing under the Interim Servicing Agreement or the Servicer under the Servicing Agreement. Such rights will include, without limitation, the right to terminate American Home Servicing under the Interim Servicing Agreement or the Servicer under the Servicing Agreement upon the occurrence of an event of default thereunder, the right to receive all remittances required to be made by American Home Servicing under the Interim Servicing Agreement or the Servicer under the Servicing Agreement, the right to receive all monthly reports and other data required to be delivered by the Servicer under the Servicing Agreement and American Home Servicing under the Interim Servicing Agreement, the right to examine the books and records of the Servicer pursuant to the terms of the Servicing Agreement and of American Home Servicing pursuant to the terms of the Interim Servicing Agreement, indemnification rights and the right to exercise certain rights of consent and approval relating to actions taken by JPMorgan Acquisition pursuant to the terms of the Servicing Agreement and the Interim Servicing Agreement. The Servicer and American Home Servicing shall make all distributions under the Servicing Agreement and the Interim Servicing Agreement, respectively to the Master Servicer by wire transfer of immediately available funds to:

Wells Fargo Bank, N.A.

ABA Number:   121-000-248

Account Name:  SAS Clearing

Account number:  3970771416

For further credit to:  J.P. Morgan Mortgage Trust 2007-S3,

        Distribution Account Number: 53166400

Notwithstanding anything in the Servicing Agreement or the Interim Servicing Agreement to the contrary, the Servicer and American Home Servicing, respectively shall furnish to the Master Servicer the monthly reports required by the Servicing Agreement and the Interim Servicing Agreement on the forms, and containing information described in such forms, attached hereto as Exhibit II at the following address:

Wells Fargo Bank, N.A.

9062 Old Annapolis Road

Columbia, Maryland 21045

Attention: Client Manager – JPMMT 2007-S3

Telecopier: (410) 715-2380

5.

Subservicing Agreement

As of the applicable Transfer Date, JPMCBNA has engaged Chase Home Finance LLC (“CHF”) to act as subservicer with respect to JPMCBNA’s servicing obligations under the Servicing Agreement. So long as JPMCBNA is not a rated servicer by Standard & Poor's, a division of The McGraw-Hill Companies, Inc. (“Standard & Poor’s”), JPMCBNA agrees that prior to replacing CHF as subservicer, other than with an affiliate of JPMCB that is a rated servicer, it will obtain written confirmation from Standard and Poor’s that such replacement of CHF as subservicer with respect  to JPMCBNA’s servicing obligations related to the Mortgage Loans will not cause the current rating on the Certificates (as defined in the Pooling and Servicing Agreement) to be withdrawn or lowered by Standard and Poor’s and agrees that any replacement subservicer shall agree to subservice in accordance with the terms of the Servicing Agreement, including but not limited to the consideration of whether to waive a prepayment penalty thereunder.

6.

Establishment of Escrow Account

The Servicer shall establish and maintain a separate Escrow Account titled “Chase Home Finance LLC, as Subservicer for JPMorgan Chase Bank, National Association, in trust for U.S. Bank National Association, as Trustee for J.P. Morgan Mortgage Trust 2007-S3 and various Mortgagors,” for funds collected and received on the Specified Mortgage Loans.

7.

Establishment of Custodial Account

The Servicer shall establish and maintain a separate Custodial Account titled “Chase Home Finance LLC, as Subservicer for JPMorgan Chase Bank, National Association, in trust for U.S. Bank National Association, as Trustee for J.P. Morgan Mortgage Trust 2007-S3,” for funds collected and received on the Specified Mortgage Loans.

8.

Indemnification by Master Servicer

The Master Servicer shall indemnify and hold harmless the Servicer, American Home Servicing and each of their affiliates, and in each case, its officers, directors and agents from and against any losses, damages, penalties, fines, forfeitures, reasonable legal fees and related costs, judgments and other costs and expenses arising out of or based upon a breach by the Master Servicer or any of its officers, directors, agents or affiliates of its obligations in connection with the preparation, filing and certification of any Form 10-K pursuant to the Pooling and Servicing Agreement or the negligence, bad faith or willful misconduct of the Master Servicer in connection therewith. In addition, the Master Servicer shall indemnify and hold harmless the Servicer, American Home Servicing and each of their affiliates, and in each case, its officers, directors and agents from and against any losses, damages, penalties, fines, forfeitures, reasonable legal fees and related costs, judgments and other costs and expenses arising out of or based upon a breach by any Servicer (as defined in the Pooling and Servicing Agreement), other than the Servicer (as defined herein), of its obligations in connection with any back-up certification (or any other back-up documents) to any certification of any Form 10-K required to be provided by the Master Servicer, but solely to the extent the Master Servicer receives amounts from such Servicer in connection with any indemnification provided by such Servicer (in each case as defined in the Pooling and Servicing Agreement) to the Master Servicer.

9.

Continuing Effect

Except as contemplated hereby, the Servicing Agreement and the Interim Servicing Agreement shall each remain in full force and effect in accordance with its terms.

10.

Governing Law

This Assignment and the rights and obligations hereunder shall be governed by and construed in accordance with the internal laws of the State of New York.

11.

Notices

Any notices or other communications permitted or required under the Agreements to be made to JPMorgan Acquisition, the Depositor, the Trustee, the Master Servicer, American Home Servicing and the Servicer shall be made in accordance with the terms of the Agreements and shall be sent to the Depositor and Trustee as follows:

In the case of JPMorgan Acquisition:

J.P. Morgan Mortgage Acquisition Corp.

270 Park Avenue, 6th Floor

New York, New York 10017

Attention: Matthew Wong

Telephone: (212) 834 3850

Facsimile: (212) 834 6591

With a copy to:

JPMorgan Chase & Co.

270 Park Avenue

New York, New York 10017

Attention: General Counsel’s Office

In the case of the Depositor:

J.P. Morgan Acceptance Corporation I

270 Park Avenue

New York, New York 10017

Attention:  J.P. Morgan Mortgage Trust 2007-S3

In the case of the Trustee:

U.S. Bank National Association

EP-MN-WS3D

60 Livingston Avenue

St. Paul, MN 55107

Attention:  J.P. Morgan Mortgage Trust 2007-S3

In the case of American Home Servicing:

American Home Mortgage Servicing, Inc.

4600 Regent Boulevard

Suite 200

Irving, Texas 75063

Attention: David Friedman

With a copy to:

American Home Mortgage Servicing, Inc.

538 Broadhollow Road

Melville, New York 11747

Attention: Alan B. Horn, General Counsel

Facsimile: (800) 209-7276

In the case of the Servicer:

JPMorgan Chase Bank, National Association

194 Wood Avenue South

Iselin, New Jersey 08830

Attention:  Bruce J. Friedman, Manager of Contract Finance

With a copy to:

JPMorgan Chase Bank, National Association

c/o Chase Home Finance LLC

194 Wood Avenue South

Iselin, New Jersey 08830

Attention:  General Counsel

In the case of the Master Servicer:

Wells Fargo Bank, N.A.

9062 Old Annapolis Road

Columbia, Maryland 21045

Attention: Client Manager – JPMMT 2007-S3

Telecopier: (410) 715-2380

or to such other address as may hereafter be furnished by the Depositor and the Trustee to the parties in accordance with the provisions of the Servicing Agreement.

12.

Ratification

Except as modified and expressly amended by this Assignment, each Agreement is in all respects ratified and confirmed, and all terms, provisions and conditions thereof shall be and remain in full force and effect.

13.

Counterparts

This Assignment may be executed in counterparts, each of which when so executed shall be deemed to be an original and all of which when taken together shall constitute one and the same instrument.

14.

Definitions

Any capitalized term used but not defined in this Assignment has the same meaning as in the Servicing Agreement.

15.

Amendments to the Servicing Agreement

The parties to the Servicing Agreement hereby agree to amend the Servicing Agreement as follows:

(a)

Section 4.04(viii) is hereby amended by replacing the reference to “Section 3.03” with “Section 3.02”; and

(b)

Section 4.05(vi) is hereby amended by replacing the reference to “Section 3.03” with “Section 3.02”.

[SIGNATURE PAGE FOLLOWS]

---

IN WITNESS WHEREOF, the parties hereto have executed this Assignment the day and year first above written.

J.P. MORGAN MORTGAGE ACQUISITION

CORP.

By: _/s/ Rosa Hyun____________________

Name: Rosa Hyun

Title: Vice President

J.P. MORGAN ACCEPTANCE CORPORATION I

By: _/s/ Rosa Hyun____________________

Name: Rosa Hyun

Title: Vice President

U.S. BANK NATIONAL ASSOCIATION, as Trustee of J.P. Morgan Mortgage Trust 2007-S3

By: _/s/ Charles F. Pedersen_______________

Name: Charles F. Pedersen

Title: Vice President

WELLS FARGO BANK, N.A., as Master Servicer

By: _/s/ Martin Reed________________

Name: Martin Reed

Title: Vice President

JPMORGAN CHASE BANK, NATIONAL ASSOCIATION, as Servicer

By: _/s/ Rita Volpe___________________

Name: Rita Volpe

Title: Vice President

---

AMERICAN HOME MORTGAGE SERVICING, INC.

By: _/s/ Alan B. Horn_________________

Name: Alan B. Horn

Title: Executive Vice President

General Counsel & Secretary

---

EXHIBIT I

Mortgage Loan Schedule

[See Schedule A to Pooling and Servicing Agreement]

---

EXHIBIT II

Exhibit IIa: Standard File Layout – Delinquency Reporting

  *The column/header names in bold are the minimum fields Wells Fargo must receive from every Servicer

Column/Header Name	Description		Decimal	Format Comment
SERVICER_LOAN_NBR	A unique number assigned to a loan by the Servicer.  This may be different than the LOAN_NBR
LOAN_NBR	A unique identifier assigned to each loan by the originator.
CLIENT_NBR	Servicer Client Number
SERV_INVESTOR_NBR	Contains a unique number as assigned by an external servicer to identify a group of loans in their system.
BORROWER_FIRST_NAME	First Name of the Borrower.
BORROWER_LAST_NAME	Last name of the borrower.
PROP_ADDRESS	Street Name and Number of Property
PROP_STATE	The state where the  property located.
PROP_ZIP	Zip code where the property is located.
BORR_NEXT_PAY_DUE_DATE	The date that the borrower's next payment is due to the servicer at the end of processing cycle, as reported by Servicer.			MM/DD/YYYY
LOAN_TYPE	Loan Type (i.e. FHA, VA, Conv)
BANKRUPTCY_FILED_DATE	The date a particular bankruptcy claim was filed.			MM/DD/YYYY
BANKRUPTCY_CHAPTER_CODE	The chapter under which the bankruptcy was filed.
BANKRUPTCY_CASE_NBR	The case number assigned by the court to the bankruptcy filing.
POST_PETITION_DUE_DATE	The payment due date once the bankruptcy has been approved by the courts			MM/DD/YYYY
BANKRUPTCY_DCHRG_DISM_DATE	The Date The Loan Is Removed From Bankruptcy. Either by Dismissal, Discharged and/or a Motion For Relief Was Granted.			MM/DD/YYYY
LOSS_MIT_APPR_DATE	The Date The Loss Mitigation Was Approved By The Servicer			MM/DD/YYYY
LOSS_MIT_TYPE	The Type Of Loss Mitigation Approved For A Loan Such As;
LOSS_MIT_EST_COMP_DATE	The Date The Loss Mitigation /Plan Is Scheduled To End/Close			MM/DD/YYYY
LOSS_MIT_ACT_COMP_DATE	The Date The Loss Mitigation Is Actually Completed			MM/DD/YYYY
FRCLSR_APPROVED_DATE	The date DA Admin sends a letter to the servicer with instructions to begin foreclosure proceedings.			MM/DD/YYYY
ATTORNEY_REFERRAL_DATE	Date File Was Referred To Attorney to Pursue Foreclosure			MM/DD/YYYY
FIRST_LEGAL_DATE	Notice of 1st legal filed by an Attorney in a Foreclosure Action			MM/DD/YYYY
FRCLSR_SALE_EXPECTED_DATE	The date by which a foreclosure sale is expected to occur.			MM/DD/YYYY
FRCLSR_SALE_DATE	The actual date of the foreclosure sale.			MM/DD/YYYY
FRCLSR_SALE_AMT	The amount a property sold for at the foreclosure sale.		2	No commas(,) or dollar signs ($)
EVICTION_START_DATE	The date the servicer initiates eviction of the borrower.			MM/DD/YYYY
EVICTION_COMPLETED_DATE	The date the court revokes legal possession of the property from the borrower.			MM/DD/YYYY
LIST_PRICE	The price at which an REO property is marketed.		2	No commas(,) or dollar signs ($)
LIST_DATE	The date an REO property is listed at a particular price.			MM/DD/YYYY
OFFER_AMT	The dollar value of an offer for an REO property.		2	No commas(,) or dollar signs ($)
OFFER_DATE_TIME	The date an offer is received by DA Admin or by the Servicer.			MM/DD/YYYY
REO_CLOSING_DATE	The date the REO sale of the property is scheduled to close.			MM/DD/YYYY
REO_ACTUAL_CLOSING_DATE	Actual Date Of REO Sale			MM/DD/YYYY
OCCUPANT_CODE	Classification of how the property is occupied.
PROP_CONDITION_CODE	A code that indicates the condition of the property.
PROP_INSPECTION_DATE	The date a  property inspection is performed.			MM/DD/YYYY
APPRAISAL_DATE	The date the appraisal was done.			MM/DD/YYYY
CURR_PROP_VAL	The current "as is" value of the property based on brokers price opinion or appraisal.		2
REPAIRED_PROP_VAL	The amount the property would be worth if repairs are completed pursuant to a broker's price opinion or appraisal.		2
If applicable:
DELINQ_STATUS_CODE	FNMA Code Describing Status of Loan
DELINQ_REASON_CODE	The circumstances which caused a borrower to stop paying on a loan.   Code indicates the reason why the loan is in default for this cycle.
MI_CLAIM_FILED_DATE	Date Mortgage Insurance Claim Was Filed With Mortgage Insurance Company.			MM/DD/YYYY
MI_CLAIM_AMT	Amount of Mortgage Insurance Claim Filed			No commas(,) or dollar signs ($)
MI_CLAIM_PAID_DATE	Date Mortgage Insurance Company Disbursed Claim Payment			MM/DD/YYYY
MI_CLAIM_AMT_PAID	Amount Mortgage Insurance Company Paid On Claim		2	No commas(,) or dollar signs ($)
POOL_CLAIM_FILED_DATE	Date Claim Was Filed With Pool Insurance Company			MM/DD/YYYY
POOL_CLAIM_AMT	Amount of Claim Filed With Pool Insurance Company		2	No commas(,) or dollar signs ($)
POOL_CLAIM_PAID_DATE	Date Claim Was Settled and The Check Was Issued By The Pool Insurer			MM/DD/YYYY
POOL_CLAIM_AMT_PAID	Amount Paid On Claim By Pool Insurance Company		2	No commas(,) or dollar signs ($)
FHA_PART_A_CLAIM_FILED_DATE	Date FHA Part A Claim Was Filed With HUD			MM/DD/YYYY
FHA_PART_A_CLAIM_AMT	Amount of FHA Part A Claim Filed		2	No commas(,) or dollar signs ($)
FHA_PART_A_CLAIM_PAID_DATE	Date HUD Disbursed Part A Claim Payment			MM/DD/YYYY
FHA_PART_A_CLAIM_PAID_AMT	Amount HUD Paid on Part A Claim		2	No commas(,) or dollar signs ($)
FHA_PART_B_CLAIM_FILED_DATE	Date FHA Part B Claim Was Filed With HUD			MM/DD/YYYY
FHA_PART_B_CLAIM_AMT	Amount of FHA Part B Claim Filed		2	No commas(,) or dollar signs ($)
FHA_PART_B_CLAIM_PAID_DATE	Date HUD Disbursed Part B Claim Payment			MM/DD/YYYY
FHA_PART_B_CLAIM_PAID_AMT	Amount HUD Paid on Part B Claim		2	No commas(,) or dollar signs ($)
VA_CLAIM_FILED_DATE	Date VA Claim Was Filed With the Veterans Admin			MM/DD/YYYY
VA_CLAIM_PAID_DATE	Date Veterans Admin. Disbursed VA Claim Payment			MM/DD/YYYY
VA_CLAIM_PAID_AMT	Amount Veterans Admin. Paid on VA Claim		2	No commas(,) or dollar signs ($)
MOTION_FOR_RELIEF_DATE	The date the Motion for Relief was filed	10		MM/DD/YYYY
FRCLSR_BID_AMT	The foreclosure sale bid amount	11		No commas(,) or dollar signs ($)
FRCLSR_SALE_TYPE	The foreclosure sales results: REO, Third Party, Conveyance to HUD/VA
REO_PROCEEDS	The net proceeds from the sale of the REO property.			No commas(,) or dollar signs ($)
BPO_DATE	The date the BPO was done.
CURRENT_FICO	The current FICO score