EXECUTION COPY

ASSIGNMENT AND ASSUMPTION AGREEMENT

        THIS ASSIGNMENT AND ASSUMPTION AGREEMENT, dated January 1, 2005, between
DLJ Mortgage Capital, Inc., a Delaware corporation (“Assignor”), and Credit
Suisse First Boston Mortgage Securities Corp., a Delaware corporation
(“Assignee”):

        For and in consideration of the sum of TEN DOLLARS ($10.00) and other
valuable consideration the receipt and sufficiency of which hereby are
acknowledged, and of the mutual covenants herein contained, the parties hereto
hereby agree as follows:

1.     The Assignor hereby grants, transfers and assigns to Assignee all of the
right, title and interest of Assignor, as Purchaser, in, to and under (a) those
certain Mortgage Loans listed on Exhibit A attached hereto (the “Mortgage
Loans”) and (b) those certain agreements listed on Exhibit B attached hereto
(the “Agreements”) with respect to the Mortgage Loans.

        The Assignor specifically reserves and does not assign to the Assignee
hereunder any and all right, title and interest in, to and under and all
obligations of the Assignor with respect to any mortgage loans subject to the
Agreements which are not the Mortgage Loans set forth on Exhibit A attached
hereto and are not the subject of this Assignment and Assumption Agreement.

2.     The Assignor warrants and represents to, and covenants with, the Assignee
that:

(a)     The Assignor is the lawful owner of the Mortgage Loans with the full
right to transfer the Mortgage Loans free from any and all claims and
encumbrances whatsoever;

(b)     The Assignor has not received notice or, and has no knowledge of, any
offsets, counterclaims or other defenses with respect to the Agreements or the
Mortgage Loans;

(c)     The Assignor has not waived or agreed to any waiver under, or agreed to
any amendment or other modification of, the Agreements or the Mortgage Loans,
including without limitation the transfer of the servicing obligations under the
Agreements. The Assignor has no knowledge of, and has not received notice of,
any waivers under or amendments or other modifications of, or assignments of
rights or obligations under or defaults under, the Agreements, or the Mortgage
Loans; and

(d)     Neither the Assignor nor anyone acting on its behalf has offered,
transferred, pledged, sold or otherwise disposed of the Mortgage Loans, any
interest in the Mortgage Loans or any other similar security to, or solicited
any offer to buy or accept a transfer, pledge or other disposition of the
Mortgage Loans, any interest in the Mortgage Loans or any other similar security
from, or otherwise approached or negotiated with respect to the Mortgage Loans,
any interest in the Mortgage Loans or any other similar security with, any
person in any manner, or made by general solicitation by means of general
advertising or in any other manner, or taken any other action which would
constitute a distribution of the Mortgage Loans under the Securities Act of 1933
(the “1933 Act”) or which would render the disposition of the Mortgage Loans a
violation of Section 5 of the 1933 Act or require registration pursuant thereto.

3.     The Assignee warrants and represents to, and covenants with, the Assignor
that:

(a)     The Assignee is a corporation duly organized, validly existing and in
good standing under the laws of the jurisdiction of its incorporation, and has
all requisite corporate power and authority to acquire, own and purchase the
Mortgage Loans;

(b)     The Assignee has full corporate power and authority to execute, deliver
and perform under this Assignment and Assumption Agreement, and to consummate
the transactions set forth herein. The execution, delivery and performance of
the Assignee of this Assignment and Assumption Agreement, and the consummation
by it of the transactions contemplated hereby, have been duly authorized by all
necessary corporate action of the Assignee. This Assignment and Assumption
Agreement has been duly executed and delivered by the Assignee and constitutes
the valid and legally binding obligation of the Assignee enforceable against the
Assignee in accordance with its respective terms;

(c)     To the best of Assignee’s knowledge, no material consent, approval,
order or authorization of, or declaration, filing or registration with, any
governmental entity is required to be obtained or made by the Assignee in
connection with the execution, delivery or performance by the Assignee of this
Assignment and Assumption Agreement, or the consummation by it of the
transactions contemplated hereby;

(d)     The Assignee agrees to be bound, as Purchaser, by all of the terms,
covenants and conditions of the Agreements and the Mortgage Loans, and from and
after the date hereof, the Assignee assumes for the benefit of the Assignor all
of the Assignor’s obligations as Purchaser thereunder, with respect to the
Mortgage Loans;

(e)     The Assignee understands that the Mortgage Loans have not been
registered under the 1933 Act or the securities laws of any state;

(f)     The purchase price being paid by the Assignee for the Mortgage Loans is
in excess of $250,000 and will be paid by cash remittance of the full purchase
price within sixty (60) days of the sale;

(g)     The Assignee is acquiring the Mortgage Loans for investment for its own
account only and not for any other person;

(h)     The Assignee considers itself a substantial, sophisticated institutional
investor having such knowledge and financial and business matters that it is
capable of evaluating the merits and the risks of investment in the Mortgage
Loans;

(i)     The Assignee has been furnished with all information regarding the
Mortgage Loans that it has requested from the Assignor;

(j)     Neither the Assignee nor anyone acting on its behalf has offered,
transferred, pledged, sold or otherwise disposed of the Mortgage Loans, an
interest in the Mortgage Loans or any other similar security to, or solicited
any offer to buy or accept a transfer, pledge or other disposition of the
Mortgage Loans, any interest in the Mortgage Loans or any other similar security
from, or otherwise approached or negotiated with respect to the Mortgage Loans,
any interest in the Mortgage Loans or any other similar security with, any
person in any manner, or made any general solicitation by means of general
advertising or in any other manner, or taken any other action which would
constitute a distribution of the Mortgage Loans under the 1933 Act or which
would render the disposition of the Mortgage Loans a violation of Section 5 of
the 1933 Act or require registration pursuant thereto, nor will it act, nor has
it authorized or will it authorize any person to act, in such manner with
respect to the Mortgage Loans; and

(k)     Either: (1) the Assignee is not an employee benefit plan (“Plan”) within
the meaning of section 3(3) of the Employee Retirement Income Security Act of
1974, as amended (“ERISA”) or a plan (also “Plan”) within the meaning of Section
4975(e)(1) of the Internal Revenue Code of 1986, as amended (“Code”), and the
Assignee is not directly or indirectly purchasing the Mortgage Loans on behalf
of, investment manager of, as named fiduciary of, as Trustee of, or with assets
of, a Plan; or (2) the Assignee’s purchase of the Mortgage Loans will not result
in a prohibited transaction under section 406 of ERISA or Section 4975 of the
Code.

[SIGNATURES BEGIN ON FOLLOWING PAGE]

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        IN WITNESS WHEREOF, the parties have caused this Assignment and
Assumption to be executed by their duly authorized officers as of the date first
above written.

DLJ MORTGAGE CAPITAL, INC.,
as Assignor CREDIT SUISSE FIRST BOSTON
MORTGAGE SECURITIES CORP.,
as Assignee

By:                                                    
         Name:
         Title:
By:                                                    
         Name:
         Title:
Taxpayer Identification Number: 13-3460798
Taxpayer Identification Number: 13-3320910

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A-1

EXHIBIT A

MORTGAGE LOAN SCHEDULE

[ATTACHED AS SCHEDULE I TO THE POOLING AND SERVICING AGREEMENT]

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B-1

EXHIBIT B

List of Agreements

[On file with Orrick, Herrington & Sutcliffe LLP]