Exhibit 10.4

                   KEYCORP REAL ESTATE CAPITAL MARKETS, INC.,
                                 Master Servicer


                                       and


                             COLUMN FINANCIAL, INC.,
                                  Sub-Servicer


                             SUB-SERVICING AGREEMENT


                          Dated as of September 1, 2007



              Credit Suisse First Boston Mortgage Securities Corp.
                  Commercial Mortgage Pass-Through Certificates
                                 Series 2007-C4

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                                TABLE OF CONTENTS

                                    ARTICLE I

                                   DEFINITIONS

Section 1.01  Defined Terms.................................................

                                   ARTICLE II

                  MASTER SERVICER'S ENGAGEMENT OF SUB-SERVICER
                      TO PERFORM SERVICING RESPONSIBILITIES

Section 2.01  Contract for Servicing; Possession of Mortgage Loan
               Documents....................................................

                                   ARTICLE III

                         SERVICING OF THE MORTGAGE LOANS

Section 3.01  Sub-Servicer to Service.......................................
Section 3.02  Merger or Consolidation of the Sub-Servicer...................
Section 3.03  Limitation on Liability of the Sub-Servicer and Others........
Section 3.04  Sub-Servicer's Resignation....................................
Section 3.05  No Transfer or Assignment of Servicing........................
Section 3.06  Indemnification...............................................
Section 3.07  Sub-Servicer Compensation with Respect to the Mortgage
               Loans........................................................

                                   ARTICLE IV

                                     DEFAULT

Section 4.01  Events of Default.............................................
Section 4.02  Waiver of Defaults............................................
Section 4.03  Other Remedies of Master Servicer.............................

                                    ARTICLE V

                                   TERMINATION

Section 5.01  Termination...................................................
Section 5.02  Termination of Duties with Respect to Specially Serviced
               Mortgage Loans...............................................

                                   ARTICLE VI

                                  MISCELLANEOUS

Section 6.01  Successor to the Sub-Servicer.................................
Section 6.02  Financial Statements..........................................
Section 6.03  Closing.......................................................
Section 6.04  Closing Documents.............................................
Section 6.05  Notices.......................................................
Section 6.06  Severability Clause...........................................
Section 6.07  Counterparts..................................................
Section 6.08  Governing Law.................................................
Section 6.09  Protection of Confidential Information........................
Section 6.10  Intention of the Parties......................................
Section 6.11  Third Party Beneficiary.......................................
Section 6.12  Successors and Assigns; Assignment of Agreement...............
Section 6.13  Waivers.......................................................
Section 6.14  Exhibits......................................................
Section 6.15  General Interpretive Principles...............................
Section 6.16  Complete Agreement............................................
Section 6.17  Further Agreement.............................................
Section 6.18  Amendments....................................................

EXHIBIT A   MORTGAGE LOAN SCHEDULE
EXHIBIT B   POOLING AND SERVICING AGREEMENT

<PAGE>

            This is a Sub-Servicing Agreement (the "Agreement"), dated as of
September 1, 2007, by and between KEYCORP REAL ESTATE CAPITAL MARKETS, INC.,
having an office at 911 Main Street, Suite 1500, Kansas City, Missouri 64105,
and its successors and assigns (the "Master Servicer"), and COLUMN FINANCIAL,
INC., having an office at 3414 Peachtree Road N.E., Suite 1140, Atlanta, Georgia
30326 (the "Sub-Servicer").

                              W I T N E S S E T H:

            WHEREAS, CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP. (the
"Depositor"), the Master Servicer, as Master Servicer No. 1, WACHOVIA BANK,
NATIONAL ASSOCIATION, as Master Servicer No. 2, MIDLAND LOAN SERVICES, INC., as
Master Servicer No. 3, NCB, FSB, as Master Servicer No. 4, ING CLARION PARTNERS,
LLC, as Special Servicer No. 1 (the "Special Servicer"), NATIONAL CONSUMER
COOPERATIVE BANK, as Special Servicer No. 2, and WELLS FARGO BANK, N.A. (the
"Trustee") have entered into that certain Pooling and Servicing Agreement dated
as of September 1, 2007, as amended, modified and restated from time to time
(the "Pooling and Servicing Agreement"), whereby the Master Servicer shall
master service certain mortgage loans on behalf of the Trustee;

            WHEREAS, Section 3.22 of the Pooling and Servicing Agreement permits
the Master Servicer to enter into agreements with sub-servicers for the
sub-servicing of mortgage loans; and

            WHEREAS, the Master Servicer desires to enter into a contract with
the Sub-Servicer with respect to certain mortgage loans (the "Mortgage Loans")
identified on Exhibit A hereto (the "Mortgage Loan Schedule").

            NOW, THEREFORE, in consideration of the mutual agreements
hereinafter set forth, and for other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the Master Servicer and
the Sub-Servicer hereby agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

            Section 1.01 Defined Terms.

            Unless otherwise specified in this Agreement, all capitalized terms
not otherwise defined herein shall have the meanings set forth in the Pooling
and Servicing Agreement. As used herein, the following terms have the meanings
assigned to them in this Section 1.01:

            "CSI": Centerline Servicing Inc.

            "Mortgage Loans": As defined in the recitals hereto.

            "Mortgage Loan Schedule": As defined in the recitals hereto.

            "Sub-Servicing Fee": With respect to the Mortgage Loans, the fee
payable pursuant to Section 3.07 of this Agreement.

            "Sub-Servicing Fee Rate": With respect to the Mortgage Loans the
rate set forth on the Mortgage Loan Schedule.

                                   ARTICLE II

                  MASTER SERVICER'S ENGAGEMENT OF SUB-SERVICER
                      TO PERFORM SERVICING RESPONSIBILITIES

            Section 2.01 Contract for Servicing; Possession of Mortgage Loan
Documents.

            The Master Servicer, by execution and delivery of this Agreement,
does hereby contract with the Sub-Servicer, subject to the terms of this
Agreement, for the servicing of the Mortgage Loans. On and after the Closing
Date, the Sub-Servicer shall hold any portion of the Servicing Files (including
without limitation, any original letter of credit to the extent such letter of
credit has been delivered to the Sub-Servicer) or the Mortgage Files in the
possession of the Sub-Servicer in trust by the Sub-Servicer, on behalf of the
Master Servicer for the benefit of the Trustee. The Sub-Servicer's possession of
any portion of the Servicing Files or the Mortgage Files shall be at the will of
the Master Servicer and the Trustee for the sole purpose of facilitating the
servicing or the supervision of servicing of the Mortgage Loans pursuant to this
Agreement, and such retention and possession by the Sub-Servicer shall be in a
custodial capacity only. Any portion of the Servicing Files or the Mortgage
Files retained by the Sub-Servicer shall be identified to reflect clearly the
ownership of the Mortgage Loans by the Trustee. The Sub-Servicer shall release
from its custody any Mortgage Files retained by it only in accordance with this
Agreement and the Pooling and Servicing Agreement.

                                   ARTICLE III

                         SERVICING OF THE MORTGAGE LOANS

            Section 3.01 Sub-Servicer to Service.

            (a) The Sub-Servicer, as an independent contractor, shall service
and administer pursuant to this Agreement on behalf of the Master Servicer and
the Trustee in the best interests of and for the benefit of the
Certificateholders in accordance with any and all applicable laws and the terms
of this Agreement and the Mortgage Loans and to the extent consistent with the
foregoing with the Servicing Standard under the Pooling and Servicing Agreement.
For the avoidance of doubt, the Sub-Servicer's obligations and rights under this
Agreement are expressly limited to the Mortgage Loans set forth in Exhibit A.
Without in any way limiting the generality of this Section 3.01(a), the parties
hereto hereby acknowledge that, except as otherwise set forth herein, any or all
of the Sub-Servicer's obligations hereunder may be performed in the
Sub-Servicer's name by CSI.

            (b) The Sub-Servicer shall perform, on behalf of the Master
Servicer, all of the obligations of the Master Servicer (with respect to the
Mortgage Loans subject to this Agreement) as set forth in those sections of the
Pooling and Servicing Agreement incorporated herein pursuant to Section 3.01(c)
of this Agreement (the "Incorporated Sections"), as modified by Section 3.01(c)
of this Agreement, and the Master Servicer shall have the same rights with
respect to the Sub-Servicer that the Trustee, the Depositor, the Underwriters,
the Rating Agencies and the Certificateholders (including, without limitation,
the right of the Special Servicer to direct the Master Servicer during certain
periods) have with respect to the Master Servicer under the Pooling and
Servicing Agreement to the extent that the Sub-Servicer is acting on behalf of
the Master Servicer hereunder and except as otherwise set forth herein. Without
limiting the foregoing, and subject to Section 3.21 of the Pooling and Servicing
Agreement as modified herein, the Sub-Servicer shall service and administer the
Mortgage Loans so long as no such mortgage loan is then a Specially Serviced
Mortgage Loan; provided, however, that the Sub-Servicer shall, under instruction
from the Special Servicer or the Master Servicer, deliver certain statements and
documents reasonably requested by the Special Servicer regarding information
held by the Sub-Servicer and continue to cooperate with the Special Servicer by
providing reasonably requested information regarding the servicing of any such
Specially Serviced Mortgage Loan. All references herein to the respective duties
of the Sub-Servicer and the Special Servicer, and to the areas in which they may
exercise discretion, shall be subject to Section 3.21 of the Pooling and
Servicing Agreement, as modified herein and to the Special Servicer's rights to
service Specially Serviced Mortgage Loans. Except as otherwise set forth below,
for purposes of this Agreement, references to the Trustee, the Depositor, the
Underwriters, the Rating Agencies, and the Certificateholders in the
Incorporated Sections shall be deemed to be references to the Master Servicer
hereunder and references to the Master Servicer in the Incorporated Sections
shall be deemed to be references to the Sub-Servicer hereunder (such
modification of the Incorporated Sections shall be referred to herein as the
"References Modification").

            (c) The following Sections of the Pooling and Servicing Agreement
listed herein and only such Sections, unless otherwise provided in this Section
3.01(c) of this Agreement, are hereby incorporated herein by reference as if
fully set forth herein, and, for purposes of this Agreement, in addition to the
References Modification, are hereby further modified as set forth below (and to
avoid any doubt, any modification is limited to its specific terms and the
section is otherwise fully incorporated herein without limitation):

                  (1) Sections 2.05, 2.06(a) and 2.06(c). The Sub-Servicer makes
            each of the representations and warranties, other than the
            representations set forth in Section 2.06(a)(viii) and Section
            2.06(a)(ix) of the Pooling and Servicing Agreement, that are made by
            the Special Servicer in Section 2.06 of the Pooling and Servicing
            Agreement, except that reference to "Special Servicer" therein shall
            be a reference to the Sub-Servicer. The Sub-Servicer is authorized
            to transact business in each state in which a Mortgaged Property is
            located, if and to the extent required by applicable law. The Master
            Servicer makes each of the representations and warranties, other
            than the representation set forth in Section 2.05 (a)(ix) of the
            Pooling and Servicing Agreement, that it makes pursuant to Section
            2.05 of the Pooling and Servicing Agreement to the Sub-Servicer.

                  (2) Section 3.03(e). The Sub-Servicer shall process any
            requests for releases of Reserve Funds (or draws under any Letter of
            Credit delivered in lieu of Reserve Funds) with respect to the
            Mortgage Loans that are Performing Mortgage Loans and then instruct
            the Master Servicer as to the amount of any related disbursement
            from the Reserve Account (or, as applicable, the amount of any
            related draw under such Letter of Credit). The Master Servicer shall
            make such disbursements from the Reserve Account (or such draw under
            the applicable Letter of Credit, as the case may be) at the
            direction of the Sub-Servicer within three Business Days following
            receipt of notice from the Sub-Servicer, unless the Master Servicer
            has determined that such disbursement is not in accordance with the
            Servicing Standard; provided that the Master Servicer shall be
            entitled to conclusively rely on the determination of the
            Sub-Servicer as to such release requests; provided, further, the
            Master Servicer shall not release any Earn-Out Reserve Funds, or
            return any related Letter of Credit delivered in lieu of Earn-Out
            Reserve Funds, without providing notice to the Special Servicer in
            accordance with Section 3.03(e) of the Pooling and Servicing
            Agreement.

                  (3) Section 3.07(d). In lieu of the Freddie Mac, Fannie Mae or
            HUD requirements with respect to the fidelity bond and insurance
            policies described in Section 3.07(d) of the Pooling and Servicing
            Agreement, the Sub-Servicer shall cause CSI to maintain CSI's
            current insurance policies and fidelity bonds without any reduction
            in coverages or amounts and as otherwise is consistent with this
            Agreement. The fidelity bond and insurance policies required
            hereunder shall also name the Master Servicer as additional insured
            and loss payee; the Master Servicer shall designate in writing to
            the Sub-Servicer how its name shall appear prior to the
            Sub-Servicer's obligation to provide any certificate of insurance.
            The Sub-Servicer shall provide a certificate of insurance to the
            Master Servicer evidencing fidelity bond and insurance coverage
            required hereunder on or before March 31 of each year, beginning
            March 31, 2008.

                  (4) Section 3.08. With respect to the Mortgage Loans, the
            Sub-Servicer shall neither approve nor consent to an assumption of
            any of the Mortgage Loans or a transfer of interest in the Mortgagor
            nor waive any restrictions contained in the Mortgage on transfer of
            an interest in the Mortgaged Property or Mortgagor or on subordinate
            financing, without the prior written consent of the Special
            Servicer. The Sub-Servicer shall process all assumption or transfer
            of interest requests or subordinate financing requests and then
            forward to the Special Servicer (with a copy to the Master Servicer)
            its recommendation, along with any information in the possession of
            the Sub-Servicer reasonably requested by the Special Servicer in
            analysis of such requests. Any assumption fees, transfer of interest
            fees and any other fees or charges (other than application fees)
            relating to an assumption or transfer of interest request with
            respect to the Mortgage Loans shall be assessed by the Sub-Servicer
            and paid as follows: 50% to the Special Servicer, 25% to the Master
            Servicer and 25% to the Sub-Servicer. The Sub-Servicer shall be
            entitled to 100% of any application fees relating to an assumption
            or transfer of interest request with respect to the Mortgage Loans.

                  (5) Section 3.11. Section 3.11 of the Pooling and Servicing
            Agreement is not incorporated herein. The sole compensation payable
            to the Sub-Servicer with respect to the Mortgage Loans is set forth
            in Section 3.07 of this Agreement and, as applicable, under Section
            3.01(c)(4), Section 3.01(c)(9) and Section 3.01(c)(10) with respect
            to fees and charges relating to assumption, transfer of interest,
            defeasance, modification, waiver and/or amendment requests with
            respect to the Mortgage Loans.

                  (6) Sections 3.12(a) and (b). With respect to the Mortgage
            Loans, the Sub-Servicer shall not prepare any report referred to in
            the Pooling and Servicing Agreement or complete any operating
            statements or rent rolls in respect of the related Mortgaged
            Properties, except that the Sub-Servicer shall complete all
            inspection reports and shall promptly (but in no event later than
            twenty (20) days after the related inspection or collection, as
            applicable) forward to the Master Servicer an electronic copy of all
            photographs included therein and all operating statements, rent
            rolls and other period financial statements collected by the
            Sub-Servicer. The Sub-Servicer will afford the Master Servicer
            reasonable cooperation with respect to any report that the
            Sub-Servicer prepares or receives in connection with Section 3.12(a)
            and Section 3.12(b) of the Pooling and Servicing Agreement, by
            providing such information as the Master Servicer may reasonably
            request in connection with the Master Servicer's responsibilities in
            Section 3.12(a) and Section 3.12(b) of the Pooling and Servicing
            Agreement. The Sub-Servicer shall (at its own expense) at all times
            use diligent, commercially reasonable efforts to obtain and deliver
            to the Master Servicer within five (5) Business Days of receipt by
            the Sub-Servicer, the annual and quarterly operating statements,
            rent rolls and other related period financial statements required to
            be delivered by the Mortgagor pursuant to the terms of the loan
            documents for the Mortgage Loans.

                  (7) Section 3.15. With respect to the Mortgage Loans serviced
            hereunder, the Sub-Servicer shall fulfill all of the obligations of
            the Master Servicer required pursuant to Section 3.15 and Section
            6.05 of the Pooling and Servicing Agreement as if the Sub-Servicer
            were the Master Servicer thereunder; provided, however, that the
            Sub-Servicer shall not be required to make available information or
            reports prepared by or entered into by the Special Servicer to the
            extent such information and reports are not in the possession of the
            Sub-Servicer. Upon reasonable prior notice, the Sub-Servicer shall
            provide to the Master Servicer, during normal business hours, access
            to its books and records related to the servicing of the Mortgage
            Loans serviced hereunder (including, at the option of the Master
            Servicer, an on-site review).

                  (8) Section 3.19(a). Section 3.19(a) of the Pooling and
            Servicing Agreement is not incorporated herein. To the extent that
            the Sub-Servicer receives any Principal Prepayments (including any
            Insurance Proceeds or Condemnation Proceeds) in respect of any
            Mortgage Loans that are Performing Mortgage Loans, the Sub-Servicer
            shall forward such amounts to the Master Servicer within two
            Business Days of receipt by the Sub-Servicer.

                  (9) Section 3.19(f). With respect to the Mortgage Loans
            serviced hereunder, the Sub-Servicer shall fulfill all of the
            obligations of the Master Servicer required pursuant to Section
            3.19(f) of the Pooling and Servicing Agreement as if the
            Sub-Servicer were the Master Servicer thereunder. The Sub-Servicer
            shall promptly notify the Master Servicer upon satisfaction of the
            requirements of Section 3.19(f) of the Pooling and Servicing
            Agreement. Any defeasance fees with respect to the Mortgage Loans
            shall be assessed by the Sub-Servicer and paid as follows: 50% to
            the Master Servicer and 50% to the Sub-Servicer.

                  (10) Section 3.20. With respect to the Mortgage Loans, the
            Sub-Servicer shall neither approve nor consent to a modification,
            waiver or amendment of any term of a Mortgage Loan (other than as
            set forth in Section 3.01(c)(4) of this Agreement and other than
            with respect to those actions specified in Section 3.20(b) of the
            Pooling and Servicing Agreement) nor waive any restrictions
            contained in the Mortgage on such modifications, waivers or
            amendments, without the prior written consent of the Special
            Servicer. The Sub-Servicer shall process all requests for
            modifications, waivers or amendments with respect to the Mortgage
            Loans and then forward to the Special Servicer (with a copy to the
            Master Servicer) its recommendation, along with any information in
            the possession of the Sub-Servicer reasonably requested by the
            Special Servicer in analysis of such requests. Any fees relating to
            requests for modifications, waivers or amendments with respect to
            the Mortgage Loans shall be assessed by the Sub-Servicer and paid as
            follows: 50% to the Special Servicer, 25% to the Master Servicer and
            25% to the Sub-Servicer.

                  (11) Section 3.21(a). The Sub-Servicer shall promptly notify
            the Master Servicer of any event or circumstance, of which the
            Sub-Servicer becomes aware, that the Sub-Servicer deems to
            constitute a Servicing Transfer Event with respect to the Mortgage
            Loans; provided, however, that in no event shall the Sub-Servicer be
            under any obligation to perform calculations or to monitor financial
            covenants with respect to the Mortgage Loans for the purposes of
            determining the existence of any such event or circumstance. The
            determination as to whether a Servicing Transfer Event has occurred
            shall be made by the Master Servicer or the Special Servicer. Upon
            receipt by the Master Servicer of notice from the Special Servicer
            that a Specially Serviced Mortgage Loan has become a Corrected
            Mortgage Loan, the Master Servicer shall promptly give the
            Sub-Servicer notice thereof and the obligation of the Sub-Servicer
            to service and administer such mortgage loan shall resume.

                  (12) Section 3.22. References to the Master Servicer shall not
            be deemed to be references to the Sub-Servicer for purposes of
            Section 3.22. Each and every one of the terms and conditions of
            Section 3.22 shall be enforceable against the Sub-Servicer in
            accordance with the terms thereof and each requirement for the
            Sub-Servicing Agreement set forth in Section 3.22 is hereby
            incorporated into the Agreement. In addition, the parties hereto
            hereby acknowledge that the Sub-Servicer has retained CSI to
            sub-service the Mortgage Loans. Subject to Section 3.22 of the
            Pooling and Servicing Agreement, the Sub-Servicer may not transfer
            sub-servicing of the Mortgage Loans to an entity other CSI without
            the consent of the Master Servicer, whose consent shall not be
            unreasonably withheld.

                  (13) Section 12.01. To the extent applicable to the
            Sub-Servicer's duties and responsibilities set forth in this Section
            3.01(c), the Sub-Servicer shall provide (and shall cause CSI to
            provide) any and all good faith cooperation to the Depositor to
            enable it to comply with Regulation AB.

                  (14) Section 12.03. Section 12.03 is incorporated in its
            entirety to the extent applicable to the Sub-Servicer's duties and
            responsibilities set forth in this Section 3.01(c).

                  (15) Section 12.05 is incorporated herein in its entirety to
            the extent applicable to the Sub-Servicer's duties and
            responsibilities set forth in this Section 3.01(c).

                  (16) Section 12.06 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall fulfill (and
            shall cause CSI to fulfill) all of the obligations of the Master
            Servicer under Section 12.06 of the Pooling and Servicing Agreement
            (including, without limitation, the preparation of the Additional
            Form 10-D Disclosure). The Sub-Servicer shall provide (and shall
            cause CSI to provide) to the Master Servicer copies of any items
            prepared by the Sub-Servicer (or by CSI, as the case may be)
            pursuant to Section 12.06 of the Pooling and Servicing Agreement no
            later than five Business Days prior to the date when such items are
            required to be provided to the Trust under the Pooling and Servicing
            Agreement.

                  (17) Section 12.07 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall provide (and
            shall cause CSI to provide) to the Trust all the reports required of
            an Additional Servicer under Section 12.07 of the Pooling and
            Servicing Agreement. To the extent that the Sub-Servicer (or CSI) is
            aware of any information that would constitute Additional Form 10-K
            Disclosure, the Sub-Servicer shall provide (and shall cause CSI to
            provide, as applicable) such information to the Trustee and the
            Depositor within the timeframe that the Master Servicer is required
            to provide such information to the Trust under the Pooling and
            Servicing Agreement. The Sub-Servicer shall provide (and shall cause
            CSI to provide) to the Master Servicer copies of any items prepared
            by the Sub-Servicer (or by CSI, as the case may be) pursuant to
            Section 12.07 of the Pooling and Servicing Agreement no later than
            five Business Days prior to the date when such items are required to
            be provided to the Trust under the Pooling and Servicing Agreement.
            The Sub-Servicer hereby acknowledges that the purpose of Section
            12.07 of the Pooling and Servicing Agreement is to facilitate the
            compliance by the Depositor with Regulation AB.

                  (18) Section 12.08 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c) (and regardless of whether the
            Sub-Servicer or CSI, as the case may be, meets the criteria set
            forth in the definition of "Servicing Function Participant" under
            the Pooling and Servicing Agreement), the Sub-Servicer shall provide
            (and shall cause CSI to provide) to the Trust a Performance
            Certification in the form set forth on Exhibit M-3 to the Pooling
            and Servicing Agreement within the timeframe set forth under the
            Pooling and Servicing Agreement. This certification may be relied
            upon by the Trustee and the Depositor in performing their respective
            obligations under Section 12.08 of the Pooling and Servicing
            Agreement but may not be otherwise used, circulated, or relied upon
            by any person other than the Trustee or the Depositor; provided that
            the Sub-Servicer shall provide (and shall cause CSI to provide) to
            the Master Servicer a copy of such Performance Certification no
            later than five Business Days prior to the date when such
            certification is required to be provided to the Trust under the
            Pooling and Servicing Agreement.

                  (19) Section 12.09 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall fulfill (and
            shall cause CSI to fulfill) all of the obligations of the Master
            Servicer under Section 12.09 of the Pooling and Servicing Agreement
            (including, without limitation, the preparation of the Form 8-K
            Disclosure Information with respect to any Reportable Event). The
            Sub-Servicer shall notify the parties to the Pooling and Servicing
            Agreement of any Reportable Event within the timeframe set forth in
            Section 12.09 of the Pooling and Servicing Agreement. The
            Sub-Servicer shall provide (and shall cause CSI to provide) to the
            Master Servicer copies of any items prepared by the Sub-Servicer (or
            by CSI, as the case may be) pursuant to Section 12.09 of the Pooling
            and Servicing Agreement no later than five Business Days prior to
            the date when such items are required to be provided to the Trust
            under the Pooling and Servicing Agreement.

                  (20) Section 12.10(b) is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall provide any
            and all good faith cooperation to the Trustee and the Depositor to
            enable the Depositor to satisfy its Exchange Act reporting
            obligations in respect of the Trust.

                  (21) Section 12.11 is incorporated herein. The Sub-Servicer
            shall provide (and shall cause CSI to provide) to the Trust an
            Officer's Certificate containing the certifications required of an
            Additional Servicer under Section 12.11 of the Pooling and Servicing
            Agreement. The Sub-Servicer shall provide (and shall cause CSI to
            provide) to the Master Servicer copies of any such Officer's
            Certificate prepared by the Sub-Servicer (or by CSI, as the case may
            be) pursuant to Section 12.11 of the Pooling and Servicing Agreement
            no later than five Business Days prior to the date when such
            Officer's Certificate is required to be provided to the Trust under
            the Pooling and Servicing Agreement.

                  (22) Section 12.12 is incorporated herein. The Sub-Servicer
            shall provide (and shall cause CSI to provide) to all parties
            specified in Section 12.12 of the Pooling and Servicing Agreement
            the reports required of Servicing Function Participant under Section
            12.12 of the Pooling and Servicing Agreement (regardless of whether
            the Sub-Servicer or CSI, as the case may be, meets the criteria set
            forth in the definition of "Servicing Function Participant" under
            the Pooling and Servicing Agreement) within the timeframe set forth
            under the Pooling and Servicing Agreement. The Sub-Servicer shall
            provide (and shall cause CSI to provide) to the Master Servicer
            copies of any reports prepared by the Sub-Servicer (or by CSI, as
            the case may be) pursuant to Section 12.12 of the Pooling and
            Servicing Agreement no later than five Business Days prior to the
            date when such reports are required to be provided to the Trust
            under the Pooling and Servicing Agreement.

                  (23) Section 12.13 is incorporated herein. The Sub-Servicer
            shall deliver (and shall cause CSI to deliver) the annual
            independent public accountants' attestation referenced in Section
            12.13 of the Pooling and Servicing Agreement (regardless of whether
            the Sub-Servicer or CSI, as the case may be, meets the criteria set
            forth in the definition of "Servicing Function Participant" under
            the Pooling and Servicing Agreement) within the timeframe that such
            attestation is required to be delivered to the Trustee and the
            Depositor under the Pooling and Servicing Agreement. The
            Sub-Servicer shall provide (and shall cause CSI to provide) to the
            Master Servicer a copy of such attestation no later than five
            Business Days prior to the date when such attestation is required to
            be provided to the Trust under the Pooling and Servicing Agreement.

                  (24) Section 12.14 is incorporated herein. References to the
            Servicing Function Participant shall be references to the
            Sub-Servicer (and, to the extent applicable to CSI's performance of
            the Sub-Servicer's duties hereunder, to CSI). References to each of
            the Trustee, the Master Servicer and the Special Servicer shall
            remain a reference to each such party.

            Section 3.02 Merger or Consolidation of the Sub-Servicer.

            The Sub-Servicer shall keep in full effect its existence, rights and
franchises as a duly formed business entity formed under the laws of the state
of its organization.

            Any Person into which the Sub-Servicer may be merged or
consolidated, or any corporation resulting from any merger, conversion or
consolidation to which the Sub-Servicer shall be a party, or any Person
succeeding to the business of the Sub-Servicer, shall be the successor of the
Sub-Servicer hereunder, without the execution or filing of any paper or any
further act on the part of any of the parties hereto, anything herein to the
contrary notwithstanding; provided, however, that the successor or surviving
Person (i) must be a company whose business includes the servicing of mortgage
loans and shall be authorized to transact business in the state or states in
which the related Mortgaged Property it is to service is situated if and to the
extent required by applicable law, (ii) must be acceptable to the Master
Servicer (in its reasonable discretion), and (iii) shall assume in writing the
obligations of the Sub-Servicer under this Agreement.

            Section 3.03 Limitation on Liability of the Sub-Servicer and Others.

            Neither the Sub-Servicer nor any of the officers, employees or
agents of the Sub-Servicer shall be under any liability to the Master Servicer
for any action taken or for refraining from the taking of any action in good
faith pursuant to this Agreement or as set forth in any writing from the Master
Servicer, or for errors in judgment; provided, however, that this provision
shall not protect the Sub-Servicer or any such person against liability to the
Master Servicer under Section 3.06, or any liability which would otherwise be
imposed by reason of any breach of the terms and conditions of this Agreement,
or against any expense or liability specifically required to be borne by such
party without right of reimbursement pursuant to the terms hereof. The
Sub-Servicer and any officer, employee or agent of the Sub-Servicer may rely in
good faith on any document of any kind that appears on its face to be properly
executed and submitted by any Person respecting any matters arising hereunder.
The Sub-Servicer shall not be under any obligation to appear in, prosecute or
defend any legal action unless such action is related to its duties under this
Agreement and, unless it is specifically required to bear the costs of such
legal action or, in its opinion does not involve it in any ultimate expense or
liability; provided, however, that the Sub-Servicer may, with the consent of the
Master Servicer, undertake any such action which it may deem necessary or
desirable in respect to this Agreement and the rights and duties of the parties
hereto. In such event, the legal expenses and costs of such action and any
liability resulting therefrom shall be expenses, costs and liabilities for which
the Master Servicer will be liable and the Sub-Servicer shall be entitled to be
reimbursed therefor from the Master Servicer upon written demand.

            Section 3.04 Sub-Servicer's Resignation.

            The Sub-Servicer may resign from the obligations and duties hereby
imposed on it at any time with thirty (30) days' written notice to the Master
Servicer.

            Section 3.05 No Transfer or Assignment of Servicing.

            With respect to the responsibility of the Sub-Servicer to service
Mortgage Loans hereunder, the Sub-Servicer acknowledges that the Master Servicer
has acted in reliance upon the adequacy of the Sub-Servicer's servicing program,
its integrity, financial standing and reputation and the continuance thereof.
Without in any way limiting the generality of this Section 3.05, the parties
hereto hereby acknowledge that, except as otherwise set forth herein, any or all
of the Sub-Servicer's obligations hereunder may be performed in the
Sub-Servicer's name by CSI and that the Sub-Servicer shall neither assign nor
transfer this Agreement or the servicing hereunder nor delegate its rights or
duties hereunder or any portion thereof to any party other than CSI without the
prior written approval of the Master Servicer (which approval shall not be
unreasonably withheld or delayed).

            Section 3.06 Indemnification.

            Notwithstanding the provisions of Section 3.03, the Master Servicer
and any director, officer, agent or employee of the Master Servicer shall be
indemnified and held harmless by the Sub-Servicer against any loss, liability or
expense in connection with any legal action incurred (i) by reason of either the
Sub-Servicer's or CSI's willful misconduct, bad faith or negligence in the
performance of or reckless disregard of the Sub-Servicer's duties hereunder or
(ii) by reason of any breach by the Sub-Servicer or CSI of any representation,
warranty, covenant or agreement made by the Sub-Servicer herein.

            The Sub-Servicer and any director, officer, employee or agent of the
Sub-Servicer shall be indemnified and held harmless by the Master Servicer
against any loss, liability or expense in connection with any legal action
incurred (i) by reason of the Master Servicer's willful misconduct, bad faith or
negligence in the performance of or reckless disregard of its duties hereunder
or (ii) by reason of any breach of any representation, warranty, covenant or
agreement made by the Master Servicer herein; provided that the Master Servicer
shall have no liability to the Sub-Servicer for any action taken at the
direction of the Sub-Servicer (or for refraining, in good faith, from the taking
of any such action) in accordance with Section 3.01(c)(2). The Master Servicer
agrees to use reasonable efforts to pursue the Trust Fund for indemnification
against any loss, liability or expense incurred by a Sub-Servicer in connection
with the performance of the Sub-Servicer's duties and obligations under this
Agreement as to which the Pooling and Servicing Agreement grants to the Master
Servicer a right to indemnification from the Trust Fund, and the Sub-Servicer
shall be entitled to any such sums actually received by the Master Servicer.

            Each indemnified party hereunder shall give prompt written notice to
the indemnitor of matters which may give rise to the liability of such
indemnitor hereunder; provided, however, that failure to give such notice shall
not relieve the indemnitor of any liability except to the extent of actual
prejudice.

            This Section 3.06 shall survive the termination of this Agreement
and the termination or resignation of the Master Servicer or the Sub-Servicer.

            Section 3.07 Sub-Servicer Compensation with Respect to the Mortgage
Loans.

            The Sub-Servicer shall be entitled to a Sub-Servicing Fee with
respect to each Mortgage Loan in an amount equal to the product of (i) the
Sub-Servicing Fee Rate, on a per annum basis and (ii) the outstanding principal
balance of the related Mortgage Loan; provided, however, that any such fee shall
be payable only to the extent that collections of interest on the Mortgage Loan
is sufficient to cover the Sub-Servicing Fee.

            The related Sub-Servicing Fee shall be payable on the Servicer
Remittance Date from monthly payments from the related Borrower and shall
include a report indicating (i) the then outstanding principal balance of the
related Mortgage Loan, (ii) the loan paid to date, (iii) the principal and
interest payment received by the Master Servicer on the related Mortgage Loan
and (iv) the amount of the related Sub-Servicing Fee.

                                   ARTICLE IV

                                     DEFAULT

            Section 4.01 Events of Default.

            "Event of Default," wherever used herein, unless the context
otherwise requires, means any one of the following events:

            (a) any failure on the part of the Sub-Servicer to (1) observe or
perform its obligations and duties with respect to a Mortgage Loan in strict
accordance with Section 3.01(c) of this Agreement which continue unremedied for
a period of five (5) days after the date on which notice of breach, requiring
the same to be remedied, shall be given to the Sub-Servicer by the Master
Servicer, or (2) in any way comply with Section 3.01(c)(13) through Section
3.01(c)(24) of this Agreement, provided that such failure was during the period
when the Trust Fund was subject to the reporting requirements of the Exchange
Act; or

            (b) any breach on the part of the Sub-Servicer of any representation
or warranty contained in Section 2.06(a) of the Pooling and Servicing Agreement
as modified by Section 3.01(c)(1) of this Agreement which materially and
adversely affects the interests of the Master Servicer or any Class of
Certificateholders and which continues unremedied for a period of thirty (30)
days after the date on which notice of such breach, requiring the same to be
remedied, shall have been given to the Sub-Servicer by the Master Servicer; or

            (c) an event of default with respect to the Master Servicer under
Section 7.01 of the Pooling and Servicing Agreement, which event of default
occurred as a direct result of the failure of the Sub-Servicer to perform any
obligation hereunder; or

            (d) a decree or order of a court or agency or supervisory authority
having jurisdiction in the premises in an involuntary case under any present or
future federal or state bankruptcy, insolvency or similar law for the
appointment of a conservator, receiver, liquidator, trustee or similar official
in any bankruptcy, insolvency, readjustment of debt, marshaling of assets and
liabilities or similar proceedings, or for the winding-up or liquidation of its
affairs, shall have been entered against the Sub-Servicer and such decree or
order shall have remained in force undischarged or unstayed for a period of
sixty (60) days; or

            (e) the Sub-Servicer shall consent to the appointment of a
conservator, receiver, liquidator, trustee or similar official in any
bankruptcy, insolvency, readjustment of debt, marshaling of assets and
liabilities or similar proceedings of or relating to the Sub-Servicer or of or
relating to all or substantially all of its property; or

            (f) the Sub-Servicer shall admit in writing its inability to pay its
debts generally as they become due, file a petition to take advantage of any
applicable bankruptcy, insolvency or reorganization statute, make an assignment
for the benefit of its creditors, voluntarily suspend payment of its
obligations, or take any corporate action in furtherance of the foregoing; or

            (g) the Sub-Servicer receives actual knowledge that (1) a Rating
Agency has qualified, downgraded or withdrawn its rating or ratings on one or
more Classes of Certificates, or (2) that a Rating Agency has placed one or more
Classes of Certificates on "rating watch negative" in contemplation of a rating
downgrade or withdrawal (and such "rating watch negative" placement shall not
have been withdrawn by such Rating Agency within sixty (60) days of the date the
Sub-Servicer obtained such actual knowledge), in the case of either of clauses
(1) or (2), citing servicing concerns with the Sub-Servicer or CSI as the sole
or material factor in such action; or

            (h) the Sub-Servicer shall assign or transfer or attempt to assign
or transfer all or part of its rights and obligations hereunder, except as
permitted by this Agreement.

            If any Event of Default shall occur and be continuing, then, and in
each and every such case, so long as such Event of Default shall not have been
remedied within any applicable cure period, the Master Servicer may terminate,
by notice in writing to the Sub-Servicer, all of the rights and obligations of
the Sub-Servicer as sub-servicer under this Agreement and in and to the Mortgage
Loans and the proceeds thereof. From and after the receipt by the Sub-Servicer
of such written notice, all authority and power of the Sub-Servicer under this
Agreement, whether with respect to the Mortgage Loans or otherwise, shall pass
to and be vested in the Master Servicer pursuant to and under this Section, and,
without limitation, the Master Servicer is hereby authorized and empowered to
execute and deliver, on behalf of and at the expense of the Sub-Servicer, as
attorney-in-fact or otherwise, any and all documents and other instruments, and
to do or accomplish all other acts or things necessary or appropriate to effect
the purposes of such notice of termination, whether to complete the transfer and
endorsement or assignment of the Mortgage Loans and related documents, or
otherwise. The Sub-Servicer agrees that if it is terminated pursuant to this
Section, it shall promptly (and in any event no later than five (5) Business
Days subsequent to its receipt of the notice of termination) provide the Master
Servicer with all documents and records (including, without limitation, those in
electronic form) requested by it to enable it to assume the Sub-Servicer's
functions hereunder, and shall cooperate with the Master Servicer in effecting
the termination of the Sub-Servicer's responsibilities and rights hereunder and
the assumption by a successor of the Sub-Servicer's obligations hereunder. All
accrued and unpaid Sub-Servicing Fees as of the date of termination shall be
paid to the Sub-Servicer.

            Section 4.02 Waiver of Defaults.

            The Master Servicer may waive any default by the Sub-Servicer in the
performance of its obligations hereunder and its consequences. Upon any such
waiver of a past default, such default shall cease to exist, and any Event of
Default arising therefrom shall be deemed to have been remedied for every
purpose of this Agreement. No such waiver shall extend to any subsequent or
other default or impair any right consequent thereon except to the extent
expressly so waived.

            Section 4.03 Other Remedies of Master Servicer.

            During the continuance of any Event of Default, so long as such
Event of Default shall not have been remedied, the Master Servicer, in addition
to the rights specified in Section 4.01, shall have the right, in its own name,
to take all actions now or hereafter existing at law, in equity or by statute to
enforce its rights and remedies (including the institution and prosecution of
all judicial, administrative and other proceedings and the filing of proofs of
claim and debt in connection therewith). Except as otherwise expressly provided
in this Agreement, no remedy provided for by this Agreement shall be exclusive
of any other remedy, and each and every remedy shall be cumulative and in
addition to any other remedy and no delay or omission to exercise any right or
remedy shall impair any such right or remedy or shall be deemed to be a waiver
of any Event of Default.

                                    ARTICLE V

                                   TERMINATION

            Section 5.01 Termination.

            Except as otherwise specifically set forth herein, the rights,
obligations and responsibilities of the Sub-Servicer shall terminate (without
payment of any penalty or termination fee) (i) upon the later of the final
payment or other liquidation (or any advance with respect thereto) of the last
Mortgage Loan and the disposition of all REO Property and the remittance of all
funds due hereunder; (ii) by mutual consent of the Sub-Servicer and the Master
Servicer in writing; (iii) at the option of any purchaser of the Mortgage Loans
pursuant to the Pooling and Servicing Agreement; or (iv) upon termination of the
Pooling and Servicing Agreement. Any notice of termination shall be in writing
and delivered to the Sub-Servicer as provided in Section 6.05 of this Agreement
and Sub-Servicer shall be paid all accrued and outstanding Sub-Servicing Fees as
of the date of termination.

            Section 5.02 Termination of Duties with Respect to Specially
Serviced Mortgage Loans.

            At such time as any of the Mortgage Loans becomes a Specially
Serviced Mortgage Loan, the obligations and duties of the Sub-Servicer set forth
herein with respect to such Specially Serviced Mortgage Loan that are required
to be performed by the Special Servicer under the Pooling and Servicing
Agreement shall cease; provided, however, that although duties of the
Sub-Servicer shall terminate to the extent transferred to the Special Servicer,
the Sub-Servicer shall retain the Mortgage Loan on its computer system so long
as the Mortgage Loan is a Specially Serviced Mortgage Loan. If a Mortgage Loan
is retained on the computer systems of the Sub-Servicer, the Mortgage Loan shall
be subject to the rights of the Special Servicer while the Mortgage Loan is a
Specially Serviced Mortgage Loan. In addition, the Sub-Servicer shall continue
to perform all of its duties hereunder with respect to a Specially Serviced
Mortgage Loan that are not required to be performed by the Special Servicer
pursuant to the Pooling and Servicing Agreement. If a Specially Serviced
Mortgage Loan becomes a Corrected Mortgage Loan, the Sub-Servicer shall commence
servicing such Corrected Mortgage Loan pursuant to the terms of this Agreement.

                                   ARTICLE VI

                                  MISCELLANEOUS

            Section 6.01 Successor to the Sub-Servicer.

            Prior to termination of the Sub-Servicer's responsibilities and
duties under this Agreement pursuant to Section 3.04, 4.01 or 5.01 of this
Agreement, the Master Servicer shall (i) succeed to and assume all of the
Sub-Servicer's responsibilities, rights, duties and obligations under this
Agreement, or (ii) appoint a successor which satisfies the criteria for a
successor Sub-Servicer in Section 3.02 of this Agreement and which shall succeed
to all rights and assume all of the responsibilities, duties and liabilities of
the Sub-Servicer under this Agreement accruing following the termination of the
Sub-Servicer's responsibilities, duties and liabilities under this Agreement.

            Section 6.02 Financial Statements.

            The Sub-Servicer shall, upon request, deliver to the Master Servicer
its most recent financial statements and, upon the request of the Master
Servicer, make available such other records relevant to the performance of the
Sub-Servicer's obligations hereunder as may be reasonably requested by the
Master Servicer to the extent required to enable the Master Servicer to fulfill
its related obligations under the Pooling and Servicing Agreement.

            Section 6.03 Closing.

            The closing for the commencement of the Sub-Servicer to perform the
servicing responsibilities under this Agreement with respect to the Mortgage
Loans shall take place on the Closing Date. At the Master Servicer's option, the
closing shall be either by telephone, confirmed by letter or wire as the parties
shall agree, or conducted in person, at such place as the parties shall agree.

            The closing shall be subject to the execution and delivery of the
Pooling and Servicing Agreement by the parties thereto.

            Section 6.04 Closing Documents.

            The Closing Documents shall consist of all of the following
documents:

            (a) to be provided by the Sub-Servicer and CSI:

                  (1) this Agreement executed by the Sub-Servicer and
            acknowledged by CSI; and

            (b) to be provided by the Master Servicer:

                  (1) this Agreement executed by the Master Servicer;

                  (2) the Mortgage Loan Schedule, with one copy to be attached
            to each counterpart of this Agreement as Exhibit A hereto; and

                  (3) the Pooling and Servicing Agreement substantially in the
            form of Exhibit B hereto.

            Section 6.05 Notices.

            All demands, notices, consents and communications hereunder shall be
in writing and shall be deemed to have been duly given when delivered to the
following addresses:

            (i) if to the Master Servicer:

            KeyCorp Real Estate Capital Markets, Inc.
            911 Main Street, Suite 1500
            Kansas City, Missouri  64105
            Facsimile No.: (816) 204-2290
            Attention: Bryan Nitcher

            with a copy to:

            Key Bank National Association
            127 Public Square
            Cleveland, Ohio  44114
            Facsimile No.: (216) 689-5681
            Attention: Robert C. Bowes

            with an additional copy to:

            Polsinelli Shalton Flanigan Suelthaus PC
            700 W. 47th Street, Suite 1000
            Kansas City, Missouri  64112
            Facsimile No.: (816) 753-1536
            Attention: Kraig Kohring

            and

            (ii) if to the Sub-Servicer:

            Column Financial, Inc.
            11 Madison Avenue
            5th Floor
            New York, New York  10010
            Attention: Larry Goland
            Attention: George Winckler

            and

            Column Financial, Inc.
            3414 Peachtree Road N.E.
            Suite 1140
            Atlanta, Georgia  30326
            Attention: Bob Barnes

            with copies to:

            Casey McCutcheon, Esq.
            Legal & Compliance Department
            Telecopy No.: (917) 326-8433

            and

            Cadwalader, Wickersham & Taft LLP
            One World Financial Center
            New York, New York  10281
            Attention:  Patrick T. Quinn

            and

            (iii) if to CSI:

            Centerline Servicing Inc.
            5221 N. O'Connor Blvd.
            Suite 600
            Irving, Texas  75039
            Attention: John Lloyd

            with a copy to:

            Centerline Servicing Inc.
            5221 N. O'Connor Blvd.
            Suite 600
            Irving, Texas  75039
            Attention: Jenna Unell

or such other address as may hereafter be furnished to the other party by like
notice.

            Section 6.06 Severability Clause.

            Any part, provision, representation or warranty of this Agreement
which is prohibited or which is held to be void or unenforceable shall be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction as to the Mortgage Loans shall not
invalidate or render unenforceable such provision in any other jurisdiction. If
the invalidity of any part, provision, representation or warranty of this
Agreement shall deprive any party of the economic benefit intended to be
conferred by this Agreement, the parties shall negotiate, in good faith, to
develop a structure the economic effect of which is nearly as possible the same
as the economic effect of this Agreement without regard to such invalidity.

            Section 6.07 Counterparts.

            This Agreement may be executed simultaneously in any number of
counterparts. Each counterpart shall be deemed to be an original, and all such
counterparts shall constitute one and the same instrument.

            Section 6.08 Governing Law.

            In order to, among other things, conform to the governing law
provision of the Pooling and Servicing Agreement, this Agreement shall be
construed in accordance with the laws of the State of New York and the
obligations, rights and remedies of the parties hereunder shall be determined in
accordance with the laws of the State of New York, except to the extent
preempted by federal law.

            Section 6.09 Protection of Confidential Information.

            The Sub-Servicer shall keep confidential and shall not divulge to
any party other than CSI, the Master Servicer, the Depositor, the Special
Servicer or the Trustee, without the Master Servicer's prior written consent,
any information pertaining to the Mortgage Loans or any borrower thereunder,
except to the extent that it is appropriate for the Sub-Servicer to do so in
working with third-party vendors, property inspectors, legal counsel, auditors,
taxing authorities or other governmental agencies or in accordance with this
Agreement.

            Section 6.10 Intention of the Parties.

            It is the intention of the parties that the Master Servicer is
conveying, and the Sub-Servicer is receiving, only a contract for servicing the
Mortgage Loans. Accordingly, the parties hereby acknowledge that the Trustee
remains the sole and absolute beneficial owner of the Mortgage Loans and all
rights related thereto.

            Section 6.11 Third Party Beneficiary.

            Each of the Depositor and the Trustee, for the benefit of the
Certificateholders, shall be a third party beneficiary under this Agreement;
provided that, except to the extent the Trustee or its designee assumes the
obligations of the Master Servicer hereunder as contemplated by Section 6.12 of
this Agreement, none of the Depositor, the Trustee, the Trust Fund, any
successor Master Servicer, or any Certificateholder shall have any duties under
this Agreement or any liabilities arising herefrom.

            Section 6.12 Successors and Assigns; Assignment of Agreement.

            This Agreement shall bind and inure to the benefit of and be
enforceable by the Sub-Servicer and the Master Servicer and the respective
successors and assigns of the Sub-Servicer and the Master Servicer. This
Agreement shall not be assigned, pledged or hypothecated by the Sub-Servicer to
a third party except as otherwise specifically provided for herein. If the
Master Servicer shall for any reason no longer act in such capacity under the
Pooling and Servicing Agreement, the Trustee or its designee may thereupon
assume all of the rights and, except to the extent they arose prior to the date
of assumption, obligations of the Master Servicer under this Agreement.

            Section 6.13 Waivers.

            No term or provision of this Agreement may be waived or modified
unless such waiver or modification is in writing and signed by the party against
whom such waiver or modification is sought to be enforced.

            Section 6.14 Exhibits.

            The exhibits to this Agreement are hereby incorporated and made a
part hereof and are an integral part of this Agreement.

            Section 6.15 General Interpretive Principles.

            The article and section headings are for convenience of a reference
only, and shall not limit or otherwise affect the meaning hereof.

            Section 6.16 Complete Agreement.

            This Agreement embodies the complete agreement between the parties
regarding the subject matter hereof and may not be varied except by a written
agreement conforming to the provisions of Section 6.18 of this Agreement. All
prior negotiations or representations of the parties are merged into this
Agreement and shall have no force or effect unless expressly stated herein.

            Section 6.17 Further Agreement.

            The Sub-Servicer and the Master Servicer each agree to execute and
deliver to the other such reasonable and appropriate additional documents,
instruments or agreements as may be necessary or appropriate to effectuate the
purposes of this Agreement.

            Section 6.18 Amendments.

            This Agreement may only be amended with the consent of the
Sub-Servicer and the Master Servicer. No amendment to the Pooling and Servicing
Agreement that purports to change the rights or obligations of the Sub-Servicer
hereunder shall be effective against the Sub-Servicer without the express
written consent of the Sub-Servicer.

                   [SIGNATURES COMMENCE ON THE FOLLOWING PAGE]

<PAGE>

            IN WITNESS WHEREOF, the Sub-Servicer and the Master Servicer have
caused their names to be signed hereto by their respective officers thereunto
duly authorized as of the date first above written.


                                       COLUMN FINANCIAL, INC.


                                          By:   /s/ Jeffrey A. Altabef
                                            --------------------------
                                             Name:  Jeffrey A. Altabef
                                             Title: Vice President


                                       KEYCORP REAL ESTATE CAPITAL MARKETS,
                                          INC.


                                          By:   /s/ Bryan Nitcher
                                            ---------------------
                                            Name:  Bryan Nitcher
                                            Title: Senior Vice President

Acknowledged and agreed:

CENTERLINE SERVICING INC.

By:   /s/ John Lloyd
   -----------------
   Name:  John Lloyd
   Title: Director

<PAGE>

                                    EXHIBIT A

                             MORTGAGE LOAN SCHEDULE

<TABLE>
<CAPTION>

                                                                   SUB-SERVICING FEE RATE
LOAN #           PROPERTY NAME                   CUT-OFF BALANCE        (BASIS POINTS)
-----------------------------------------------------------------------------------------
<S>      <C>                       <C>           <C>               <C>
  13     Grove Square Shopping Center             $26,000,000.00            1.25
  15     Hillside Village Shopping Center         $23,200,000.00            1.25
  18     Egizii Portfolio                         $21,865,362.71            1.25
  23     Champions Park Apartments                $15,300,000.00            1.25
  25     The Madison Hotel                        $14,687,681.46            1.25
  26     University Square                        $13,750,000.00            1.25
  28     University Centre I                      $13,400,000.00            1.25
  30     Champions Centre Apartments              $13,000,000.00            1.25
  32     Temescal Plaza                           $12,700,000.00            1.25
  34     565 Metro Place                          $12,235,000.00            1.25
  36     RV Dakota Ridge RV Park                   $5,980,000.00            1.25
  37     RV Elk Meadows RV Park                    $3,941,500.00            1.25
  38     RV Spruce Lake RV Park                    $2,047,500.00            1.25
  52     Northridge Shopping Center                $8,800,000.00            1.25
  84     Design Market                             $4,987,672.16            1.25
  88     City Center MOB                           $4,662,000.00            1.25
  91     Prominence Shops at Liberty Park          $4,252,176.98            1.25
  113    Comfort Inn & Suites Mansfield            $3,467,310.40            1.25
  118    Santa Fe Trails Apartments                $3,230,000.00            1.25
  119    Sleep Inn & Suites Metairie               $3,093,518.63            1.25
  142    Providence Plaza & Shoppes at Midtown     $2,395,787.95            1.25
  143    Dunn Commons                              $2,354,081.92            1.25
  154    3100 University Boulevard                 $2,048,015.71            1.25
  179    Office Depot Greensboro                   $1,600,000.00            1.25

</TABLE>
<PAGE>

                                    EXHIBIT B

                         POOLING AND SERVICING AGREEMENT

                                 See Exhibit 4.1


<PAGE>


                      WACHOVIA BANK, NATIONAL ASSOCIATION,
                                 Master Servicer


                                       and


                             COLUMN FINANCIAL, INC.,
                                  Sub-Servicer



                             SUB-SERVICING AGREEMENT

                          Dated as of September 1, 2007





              Credit Suisse First Boston Mortgage Securities Corp.
                  Commercial Mortgage Pass-Through Certificates
                                 Series 2007-C4


<PAGE>

                                TABLE OF CONTENTS


                                    ARTICLE I

                                   DEFINITIONS

Section 1.01  Defined Terms.................................................


                                   ARTICLE II

                 MASTER SERVICER'S ENGAGEMENT OF SUB-SERVICER
                      TO PERFORM SERVICING RESPONSIBILITIES

Section 2.01  Contract for Servicing; Possession of Mortgage Loan
               Documents....................................................


                                   ARTICLE III

                         SERVICING OF THE MORTGAGE LOANS

Section 3.01  Sub-Servicer to Service.......................................
Section 3.02  Merger or Consolidation of the Sub-Servicer...................
Section 3.03  Limitation on Liability of the Sub-Servicer and Others........
Section 3.04  Sub-Servicer's Resignation....................................
Section 3.05  No Transfer or Assignment of Servicing........................
Section 3.06  Indemnification...............................................
Section 3.07  Sub-Servicer Compensation with Respect to the Mortgage
               Loans........................................................


                                   ARTICLE IV

                                     DEFAULT

Section 4.01  Events of Default.............................................
Section 4.02  Waiver of Defaults............................................
Section 4.03  Other Remedies of Master Servicer.............................


                                    ARTICLE V

                                   TERMINATION

Section 5.01  Termination...................................................
Section 5.02  Termination of Duties with Respect to Specially Serviced
               Mortgage Loans...............................................


                                   ARTICLE VI

                                  MISCELLANEOUS

Section 6.01  Successor to the Sub-Servicer.................................
Section 6.02  Financial Statements..........................................
Section 6.03  Closing.......................................................
Section 6.04  Closing Documents.............................................
Section 6.05  Notices.......................................................
Section 6.06  Severability Clause...........................................
Section 6.07  Counterparts..................................................
Section 6.08  Governing Law.................................................
Section 6.09  Protection of Confidential Information........................
Section 6.10  Intention of the Parties......................................
Section 6.11  Third Party Beneficiary.......................................
Section 6.12  Successors and Assigns; Assignment of Agreement...............
Section 6.13  Waivers.......................................................
Section 6.14  Exhibits......................................................
Section 6.15  General Interpretive Principles...............................
Section 6.16  Complete Agreement............................................
Section 6.17  Further Agreement.............................................
Section 6.18  Amendments....................................................

EXHIBIT A   MORTGAGE LOAN SCHEDULE                                   A-1
EXHIBIT B   MASTER SERVICER REPRESENTATIONS
            AND WARRANTIES                                           B-1
EXHIBIT C   FORM OF SECRETARY'S CERTIFICATE                          C-1
EXHIBIT D   POOLING AND SERVICING AGREEMENT                          D-1

<PAGE>

            This is a Sub-Servicing Agreement (the "Agreement"), dated as of
September 1, 2007, by and between WACHOVIA BANK, NATIONAL ASSOCIATION, having an
office at 8739 Research Drive URP4, Charlotte, North Carolina 28262, and its
successors and assigns (the "Master Servicer"), and COLUMN FINANCIAL, INC.,
having an office at 3414 Peachtree Road N.E., Suite 1140, Atlanta, Georgia 30326
(the "Sub-Servicer").

                              W I T N E S S E T H:

            WHEREAS, CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES CORP., as
Depositor (the "Depositor"), KEYCORP REAL ESTATE CAPITAL MARKETS, INC., as
Master Servicer No. 1 (the "KRECM Master Servicer"), the Master Servicer, as
Master Servicer No. 2, MIDLAND LOAN SERVICES, INC., as Master Servicer No. 3,
NCB, FSB, as Master Servicer No. 4, ING CLARION PARTNERS, LLC, as Special
Servicer No. 1 (the "Special Servicer"), NATIONAL CONSUMER COOPERATIVE BANK, as
Special Servicer No. 2 and WELLS FARGO BANK, N.A., as Trustee (the "Trustee")
have entered into that certain Pooling and Servicing Agreement dated as of
September 1, 2007, as amended, modified and restated from time to time (the
"Pooling and Servicing Agreement"), whereby the Master Servicer shall master
service certain mortgage loans on behalf of the Trustee;

            WHEREAS, Section 3.22 of the Pooling and Servicing Agreement permits
the Master Servicer to enter into agreements with sub-servicers for the
sub-servicing of mortgage loans; and

            WHEREAS, the Master Servicer desires to enter into a contract with
the Sub-Servicer with respect to certain mortgage loans (the "Mortgage Loans")
identified on Exhibit A hereto (the "Mortgage Loan Schedule").

            NOW, THEREFORE, in consideration of the mutual agreements
hereinafter set forth, and for other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the Master Servicer and
the Sub-Servicer hereby agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

            Section 1.01 Defined Terms.

            Unless otherwise specified in this Agreement, all capitalized terms
not otherwise defined herein shall have the meanings set forth in the Pooling
and Servicing Agreement. As used herein, the following terms have the meanings
assigned to them in this Section 1.01:

            "CSI": Centerline Servicing Inc.

            "Mortgage Loans": As defined in the recitals hereto.

            "Mortgage Loan Schedule": As defined in the recitals hereto.

            "Servicing Fee": With respect to the Mortgage Loans, the fee payable
pursuant to Section 3.07 of this Agreement.

            "Sub-Servicing Fee Rate": With respect to the Mortgage Loans the
rate set forth on the Mortgage Loan Schedule.

                                   ARTICLE II

                  MASTER SERVICER'S ENGAGEMENT OF SUB-SERVICER
                      TO PERFORM SERVICING RESPONSIBILITIES

            Section 2.01 Contract for Servicing; Possession of Mortgage Loan
Documents.

            The Master Servicer, by execution and delivery of this Agreement,
does hereby contract with the Sub-Servicer, subject to the terms of this
Agreement, for the servicing of the Mortgage Loans. On and after the Closing
Date, the Sub-Servicer shall hold any portion of the Servicing Files (including
without limitation, any original letter of credit to the extent such letter of
credit has been delivered to the Sub-Servicer) or the Mortgage Files in the
possession of the Sub-Servicer in trust by the Sub-Servicer, on behalf of the
Master Servicer for the benefit of the Trustee. The Sub-Servicer's possession of
any portion of the Servicing Files or the Mortgage Files shall be at the will of
the Master Servicer and the Trustee for the sole purpose of facilitating the
servicing or the supervision of servicing of the Mortgage Loans pursuant to this
Agreement, and such retention and possession by the Sub-Servicer shall be in a
custodial capacity only. Any portion of the Servicing Files or the Mortgage
Files retained by the Sub-Servicer shall be identified to reflect clearly the
ownership of the Mortgage Loans by the Trustee. The Sub-Servicer shall release
from its custody any Mortgage Files retained by it only in accordance with this
Agreement and the Pooling and Servicing Agreement.

                                   ARTICLE III

                         SERVICING OF THE MORTGAGE LOANS

            Section 3.01 Sub-Servicer to Service.

            (a) The Sub-Servicer, as an independent contractor, shall service
and administer pursuant to this Agreement on behalf of the Master Servicer and
the Trustee in the best interests of and for the benefit of the
Certificateholders in accordance with any and all applicable laws and the terms
of this Agreement and the Mortgage Loans and to the extent consistent with the
foregoing with the Servicing Standard under the Pooling and Servicing Agreement.
For the avoidance of doubt, the Sub-Servicer's obligations and rights under this
Agreement are expressly limited to the Mortgage Loans set forth in Exhibit A.
Without in any way limiting the generality of this Section 3.01(a), the parties
hereto hereby acknowledge that, except as otherwise set forth herein, any or all
of the Sub-Servicer's obligations hereunder may be performed in the
Sub-Servicer's name by CSI, provided, however, the Sub-Servicer shall remain
liable to the Master Servicer under this Agreement for performance of its duties
hereunder whether or not such duties are performed by the Sub-Servicer.

            (b) The Sub-Servicer shall perform, on behalf of the Master
Servicer, all of the obligations of the Master Servicer (with respect to the
Mortgage Loans subject to this Agreement) as set forth in those sections of the
Pooling and Servicing Agreement incorporated herein pursuant to Section 3.01(c)
of this Agreement (the "Incorporated Sections"), as modified by Section 3.01(c)
of this Agreement, and the Master Servicer shall have the same rights with
respect to the Sub-Servicer that the Trustee, the Depositor, the Underwriters,
the Rating Agencies and the Certificateholders (including, without limitation,
the right of the Special Servicer to direct the Master Servicer during certain
periods) have with respect to the Master Servicer under the Pooling and
Servicing Agreement to the extent that the Sub-Servicer is acting on behalf of
the Master Servicer hereunder and except as otherwise set forth herein. Without
limiting the foregoing, and subject to Section 3.21 of the Pooling and Servicing
Agreement as modified herein, the Sub-Servicer shall service and administer the
Mortgage Loans so long as no such mortgage loan is then a Specially Serviced
Mortgage Loan; provided, however, that the Sub-Servicer shall, under instruction
from the Special Servicer or the Master Servicer, deliver certain statements and
documents reasonably requested by the Special Servicer regarding information
held by the Sub-Servicer and continue to cooperate with the Special Servicer by
providing reasonably requested information regarding the servicing of any such
Specially Serviced Mortgage Loan. All references herein to the respective duties
of the Sub-Servicer and the Special Servicer, and to the areas in which they may
exercise discretion, shall be subject to Section 3.21 of the Pooling and
Servicing Agreement, as modified herein and to the Special Servicer's rights to
service Specially Serviced Mortgage Loans. Except as otherwise set forth below,
for purposes of this Agreement, references to the Trustee, the Depositor, the
Underwriters, the Rating Agencies, and the Certificateholders in the
Incorporated Sections shall be deemed to be references to the Master Servicer
hereunder and references to the Master Servicer in the Incorporated Sections
shall be deemed to be references to the Sub-Servicer hereunder (such
modification of the Incorporated Sections shall be referred to herein as the
"References Modification").

            (c) The following Sections of the Pooling and Servicing Agreement
listed herein and only such Sections, unless otherwise provided in this Section
3.01(c) of this Agreement, are hereby incorporated herein by reference as if
fully set forth herein, and, for purposes of this Agreement, in addition to the
References Modification, are hereby further modified as set forth below (and to
avoid any doubt, any modification is limited to its specific terms and the
section is otherwise fully incorporated herein without limitation):

                  (1) Sections 2.05 and 2.06. The Sub-Servicer makes each of the
            representations and warranties, other than the representations set
            forth in Section 2.06(a)(viii) of the Pooling and Servicing
            Agreement, that are made by the Special Servicer in Section 3.24 of
            the Pooling and Servicing Agreement, except that reference to
            "Special Servicer" therein shall be a reference to the Sub-Servicer.
            The Sub-Servicer is authorized to transact business in each state in
            which a Mortgaged Property is located, if and to the extent required
            by applicable law. The Master Servicer makes each of the
            representations and warranties set forth on Exhibit B hereto to the
            Sub-Servicer.

                  (2) The Sub-Servicer shall process any requests for releases
            of Reserve Funds (or draws under any Letter of Credit delivered in
            lieu of Reserve Funds) with respect to the Mortgage Loans that are
            Performing Mortgage Loans the Master Servicer is responsible for
            processing pursuant to the Pooling and Servicing Agreement and then
            recommend to the Master Servicer the amount of any related
            disbursement from the Reserve Account (or, as applicable, the amount
            of any related draw under such Letter of Credit), which
            recommendation will be non-binding. The Master Servicer shall make
            disbursements from the Reserve Account (or draw under the applicable
            Letter of Credit, as the case may be) within three Business Days
            following receipt of the Sub-Servicer's recommendation with respect
            to such request.

                  (3) Section 3.07(d). In lieu of the Freddie Mac, Fannie Mae or
            HUD requirements with respect to the fidelity bond and insurance
            policies described in Section 3.07(d) of the Pooling and Servicing
            Agreement, the Sub-Servicer shall cause CSI to maintain CSI's
            current insurance policies and fidelity bonds without any reduction
            in coverages or amounts and as otherwise is consistent with this
            Agreement. The fidelity bond and insurance policies required
            hereunder shall also name the Master Servicer as additional insured
            and loss payee; the Master Servicer shall designate in writing to
            the Sub-Servicer how its name shall appear prior to the
            Sub-Servicer's obligation to provide any certificate of insurance.
            The Sub-Servicer shall provide a certificate of insurance to the
            Master Servicer evidencing fidelity bond and insurance coverage
            required hereunder on or before March 31 of each year, beginning
            March 31, 2008.

                  (4) Section 3.08. The Sub-Servicer shall collect all
            assumption or transfer of interest requests or subordinate financing
            requests and related documentation from the related Borrower and
            then forward to the Special Servicer (with a copy to the Master
            Servicer) such requests and related documentation. Any assumption
            fees, transfer of interest fees and any other fees or charges (other
            than application fees) relating to an assumption or transfer of
            interest request with respect to the Mortgage Loans shall be paid as
            follows: 50% to the Special Servicer, 25% to the Master Servicer and
            25% to the Sub-Servicer. The Sub-Servicer shall be entitled to 100%
            of any application fees relating to an assumption or transfer of
            interest request with respect to the Mortgage Loans.

                  (5) Section 3.11. Section 3.11 of the Pooling and Servicing
            Agreement is not incorporated herein. The sole compensation payable
            to the Sub-Servicer with respect to the Mortgage Loans is set forth
            in Section 3.07 of this Agreement and, as applicable, under Section
            3.01(c)(4), Section 3.01(c)(9) and Section 3.01(c)(10) with respect
            to fees and charges relating to assumption, transfer of interest,
            defeasance, modification, waiver and/or amendment requests with
            respect to the Mortgage Loans.

                  (6) Sections 3.12(a) (b) (c) (d). With respect to the Mortgage
            Loans, the Sub-Servicer shall not prepare any report referred to in
            the Pooling and Servicing Agreement or complete any operating
            statements or rent rolls in respect of the related Mortgaged
            Properties, except that the Sub-Servicer shall complete all
            inspection reports and shall promptly (but in no event later than
            twenty (20) days after the related inspection or collection, as
            applicable) forward to the Master Servicer an electronic copy of all
            photographs included therein and all operating statements, rent
            rolls and other period financial statements collected by the
            Sub-Servicer. The Sub-Servicer will afford the Master Servicer
            reasonable cooperation with respect to any report that the
            Sub-Servicer prepares or receives in connection with Section 3.12(a)
            and Section 3.12(b) (c) and (d) of the Pooling and Servicing
            Agreement, by providing such information as the Master Servicer may
            reasonably request in connection with the Master Servicer's
            responsibilities in Section 3.12(a) (c) and (d) and Section 3.12(b)
            of the Pooling and Servicing Agreement. The Sub-Servicer shall (at
            its own expense) at all times use diligent, commercially reasonable
            efforts to obtain and deliver to the Master Servicer within five (5)
            Business Days of receipt by the Sub-Servicer, the annual and
            quarterly operating statements, rent rolls and other related period
            financial statements required to be delivered by the Mortgagor
            pursuant to the terms of the loan documents for the Mortgage Loans.

                  (7) Section 3.15. With respect to the Mortgage Loans serviced
            hereunder, the Sub-Servicer shall fulfill all of the obligations of
            the Master Servicer required pursuant to Section 3.15 and Section
            6.05 of the Pooling and Servicing Agreement as if the Sub-Servicer
            were the Master Servicer thereunder; provided, however, that the
            Sub-Servicer shall not be required to make available information or
            reports prepared by or entered into by the Special Servicer to the
            extent such information and reports are not in the possession of the
            Sub-Servicer. Upon reasonable prior notice, the Sub-Servicer shall
            provide to the Master Servicer, during normal business hours, access
            to its books and records related to the servicing of the Mortgage
            Loans serviced hereunder (including, at the option of the Master
            Servicer, an on-site review).

                  (8) Section 3.19(f). With respect to the Mortgage Loans
            serviced hereunder, the Sub-Servicer shall fulfill all of the
            obligations of the Master Servicer required pursuant to Section
            3.19(f) of the Pooling and Servicing Agreement as if the
            Sub-Servicer were the Master Servicer thereunder. The Sub-Servicer
            shall promptly notify the Master Servicer upon satisfaction of the
            requirements of Section 3.19(f) of the Pooling and Servicing
            Agreement. Any defeasance fees with respect to the Mortgage Loans
            shall be assessed by the Sub-Servicer and paid as follows: 50% to
            the Master Servicer and 50% to the Sub-Servicer.

                  (9) Section 3.20. With respect to the Mortgage Loans, the
            Sub-Servicer shall neither approve nor consent to a modification,
            waiver or amendment of any term of a Mortgage Loan (other than as
            set forth in Section 3.01(c)(4) of this Agreement and other than
            with respect to those actions specified in Section 3.20(e) of the
            Pooling and Servicing Agreement) nor waive any restrictions
            contained in the Mortgage on such modifications, waivers or
            amendments, without the prior written consent of the Special
            Servicer. The Sub-Servicer shall collect from the related Borrower
            all requests for modifications, waivers or amendments with respect
            to the Mortgage Loans and all related documentation and then forward
            to the Special Servicer (with a copy to the Master Servicer) such
            requests and documentation. Any fees relating to requests for
            modifications, waivers or amendments with respect to the Mortgage
            Loans shall be paid as follows: 50% to the Special Servicer, 25% to
            the Master Servicer and 25% to the Sub-Servicer.

                  (10) Section 3.21(a). The Sub-Servicer shall promptly notify
            the Master Servicer of any event or circumstance, of which the
            Sub-Servicer becomes aware, that the Sub-Servicer deems to
            constitute a Servicing Transfer Event with respect to the Mortgage
            Loans; provided, however, that in no event shall the Sub-Servicer be
            under any obligation to perform calculations or to monitor financial
            covenants with respect to the Mortgage Loans for the purposes of
            determining the existence of any such event or circumstance. The
            determination as to whether a Servicing Transfer Event has occurred
            shall be made by the Master Servicer or the Special Servicer. Upon
            receipt by the Master Servicer of notice from the Special Servicer
            that a Specially Serviced Mortgage Loan has become a Corrected
            Mortgage Loan, the Master Servicer shall promptly give the
            Sub-Servicer notice thereof and the obligation of the Sub-Servicer
            to service and administer such mortgage loan shall resume.

                  (11) Section 3.22. References to the Master Servicer shall not
            be deemed to be references to the Sub-Servicer for purposes of
            Section 3.22. Each and every one of the terms and conditions of
            Section 3.22 shall be enforceable against the Sub-Servicer in
            accordance with the terms thereof and each requirement for the
            Sub-Servicing Agreement set forth in Section 3.22 is hereby
            incorporated into the Agreement. In addition, the parties hereto
            hereby acknowledge that the Sub-Servicer has retained CSI to
            sub-service the Mortgage Loans. Subject to Section 3.22 of the
            Pooling and Servicing Agreement, the Sub-Servicer may not transfer
            sub-servicing of the Mortgage Loans to an entity other than CSI
            without the consent of the Master Servicer, whose consent shall not
            be unreasonably withheld. In addition, to the extent the
            sub-servicing arrangement between the Sub-Servicer and CSI with
            respect to the Mortgage Loans is terminated for any reason, the
            Sub-Servicer shall retain an entity listed on S&P's Select Servicer
            List as a U.S. Commercial Mortgage Master Servicer to sub-service
            the Mortgage Loans.

                  (12) Section 12.01. To the extent applicable to the
            Sub-Servicer's duties and responsibilities set forth in this Section
            3.01(c), the Sub-Servicer shall provide (and shall cause CSI to
            provide) any and all good faith cooperation to the Depositor to
            enable it to comply with Regulation AB.

                  (13) Section 12.03. Section 12.03 is incorporated in its
            entirety to the extent applicable to the Sub-Servicer's duties and
            responsibilities set forth in this Section 3.01(c).

                  (14) Section 12.05 is incorporated herein in its entirety to
            the extent applicable to the Sub-Servicer's duties and
            responsibilities set forth in this Section 3.01(c).

                  (15) Section 12.06 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall fulfill (and
            shall cause CSI to fulfill) all of the obligations of the Master
            Servicer under Section 12.06 of the Pooling and Servicing Agreement
            (including, without limitation, the preparation of the Additional
            Form 10-D Disclosure). The Sub-Servicer shall provide (and shall
            cause CSI to provide) to the Master Servicer copies of any items
            prepared by the Sub-Servicer (or by CSI, as the case may be)
            pursuant to Section 12.06 of the Pooling and Servicing Agreement no
            later than five Business Days prior to the date when such items are
            required to be provided to the Trust under the Pooling and Servicing
            Agreement.

                  (16) Section 12.07 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall provide (and
            shall cause CSI to provide) to the Trust all the reports required of
            an Additional Servicer under Section 12.07 of the Pooling and
            Servicing Agreement. To the extent that the Sub-Servicer (or CSI) is
            aware of any information that would constitute Additional Form 10-K
            Disclosure, the Sub-Servicer shall provide (and shall cause CSI to
            provide, as applicable) such information to the Trustee and the
            Depositor within the timeframe that the Master Servicer is required
            to provide such information to the Trust under the Pooling and
            Servicing Agreement. The Sub-Servicer shall provide (and shall cause
            CSI to provide) to the Master Servicer copies of any items prepared
            by the Sub-Servicer (or by CSI, as the case may be) pursuant to
            Section 12.07 of the Pooling and Servicing Agreement no later than
            five Business Days prior to the date when such items are required to
            be provided to the Trust under the Pooling and Servicing Agreement.
            The Sub-Servicer hereby acknowledges that the purpose of Section
            12.07 of the Pooling and Servicing Agreement is to facilitate the
            compliance by the Depositor with Regulation AB.

                  (17) Section 12.08 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c) (and regardless of whether the
            Sub-Servicer or CSI, as the case may be, meets the criteria set
            forth in the definition of "Servicing Function Participant" under
            the Pooling and Servicing Agreement), the Sub-Servicer shall provide
            (and shall cause CSI to provide) to the Trust a Performance
            Certification in the form set forth on Exhibit M-3 to the Pooling
            and Servicing Agreement within the timeframe set forth under the
            Pooling and Servicing Agreement. This certification may be relied
            upon by the Trustee and the Depositor in performing their respective
            obligations under Section 12.08 of the Pooling and Servicing
            Agreement but may not be otherwise used, circulated, or relied upon
            by any person other than the Trustee or the Depositor; provided that
            the Sub-Servicer shall provide (and shall cause CSI to provide) to
            the Master Servicer a copy of such Performance Certification no
            later than five Business Days prior to the date when such
            certification is required to be provided to the Trust under the
            Pooling and Servicing Agreement.

                  (18) Section 12.09 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall fulfill (and
            shall cause CSI to fulfill) all of the obligations of the Master
            Servicer under Section 12.09 of the Pooling and Servicing Agreement
            (including, without limitation, the preparation of the Form 8-K
            Disclosure Information with respect to any Reportable Event). The
            Sub-Servicer shall notify the parties to the Pooling and Servicing
            Agreement of any Reportable Event within the timeframe set forth in
            Section 12.09 of the Pooling and Servicing Agreement. The
            Sub-Servicer shall provide (and shall cause CSI to provide) to the
            Master Servicer copies of any items prepared by the Sub-Servicer (or
            by CSI, as the case may be) pursuant to Section 12.09 of the Pooling
            and Servicing Agreement no later than five Business Days prior to
            the date when such items are required to be provided to the Trust
            under the Pooling and Servicing Agreement.

                  (19) Section 12.10 is incorporated herein. To the extent
            applicable to the Sub-Servicer's duties and responsibilities set
            forth in this Section 3.01(c), the Sub-Servicer shall provide any
            and all good faith cooperation to the Trustee and the Depositor to
            enable the Depositor to satisfy its Exchange Act reporting
            obligations in respect of the Trust.

                  (20) Section 12.11 is incorporated herein. The Sub-Servicer
            shall provide (and shall cause CSI to provide) to the Trust an
            Officer's Certificate containing the certifications required of an
            Additional Servicer under Section 12.11 of the Pooling and Servicing
            Agreement. The Sub-Servicer shall provide (and shall cause CSI to
            provide) to the Master Servicer copies of any such Officer's
            Certificate prepared by the Sub-Servicer (or by CSI, as the case may
            be) pursuant to Section 12.11 of the Pooling and Servicing Agreement
            no later than five Business Days prior to the date when such
            Officer's Certificate is required to be provided to the Trust under
            the Pooling and Servicing Agreement.

                  (21) Section 12.12 is incorporated herein. The Sub-Servicer
            shall provide (and shall cause CSI to provide) to all parties
            specified in Section 12.12 of the Pooling and Servicing Agreement
            the reports required of Servicing Function Participant under Section
            12.12 of the Pooling and Servicing Agreement (regardless of whether
            the Sub-Servicer or CSI, as the case may be, meets the criteria set
            forth in the definition of "Servicing Function Participant" under
            the Pooling and Servicing Agreement) within the timeframe set forth
            under the Pooling and Servicing Agreement. The Sub-Servicer shall
            provide (and shall cause CSI to provide) to the Master Servicer
            copies of any reports prepared by the Sub-Servicer (or by CSI, as
            the case may be) pursuant to Section 12.12 of the Pooling and
            Servicing Agreement no later than five Business Days prior to the
            date when such reports are required to be provided to the Trust
            under the Pooling and Servicing Agreement.

                  (22) Section 12.13 is incorporated herein. The Sub-Servicer
            shall deliver (and shall cause CSI to deliver) the annual
            independent public accountants' attestation referenced in Section
            12.13 of the Pooling and Servicing Agreement (regardless of whether
            the Sub-Servicer or CSI, as the case may be, meets the criteria set
            forth in the definition of "Servicing Function Participant" under
            the Pooling and Servicing Agreement) within the timeframe that such
            attestation is required to be delivered to the Trustee and the
            Depositor under the Pooling and Servicing Agreement. The
            Sub-Servicer shall provide (and shall cause CSI to provide) to the
            Master Servicer a copy of such attestation no later than five
            Business Days prior to the date when such attestation is required to
            be provided to the Trust under the Pooling and Servicing Agreement.

                  (23) Section 12.14 is incorporated herein. References to the
            Servicing Function Participant shall be references to the
            Sub-Servicer (and, to the extent applicable to CSI's performance of
            the Sub-Servicer's duties hereunder, to CSI). References to each of
            the Trustee, the Master Servicer and the Special Servicer shall
            remain a reference to each such party.

            Section 3.02 Merger or Consolidation of the Sub-Servicer.

            The Sub-Servicer shall keep in full effect its existence, rights and
franchises as a duly formed business entity formed under the laws of the state
of its organization.

            Any Person into which the Sub-Servicer may be merged or
consolidated, or any corporation resulting from any merger, conversion or
consolidation to which the Sub-Servicer shall be a party, or any Person
succeeding to the business of the Sub-Servicer, shall be the successor of the
Sub-Servicer hereunder, without the execution or filing of any paper or any
further act on the part of any of the parties hereto, anything herein to the
contrary notwithstanding; provided, however, that the successor or surviving
Person (i) must be a company whose business includes the servicing of mortgage
loans and shall be authorized to transact business in the state or states in
which the related Mortgaged Property it is to service is situated if and to the
extent required by applicable law, (ii) must be acceptable to the Master
Servicer (in its reasonable discretion), and (iii) shall assume in writing the
obligations of the Sub-Servicer under this Agreement.

            Section 3.03 Limitation on Liability of the Sub-Servicer and Others.

            Neither the Sub-Servicer nor any of the officers, employees or
agents of the Sub-Servicer shall be under any liability to the Master Servicer
for any action taken or for refraining from the taking of any action in good
faith pursuant to this Agreement or as set forth in any writing from the Master
Servicer, or for errors in judgment; provided, however, that this provision
shall not protect the Sub-Servicer or any such person against liability to the
Master Servicer under Section 3.06, or any liability which would otherwise be
imposed by reason of any breach of the terms and conditions of this Agreement,
or against any expense or liability specifically required to be borne by such
party without right of reimbursement pursuant to the terms hereof. The
Sub-Servicer and any officer, employee or agent of the Sub-Servicer may rely in
good faith on any document of any kind that appears on its face to be properly
executed and submitted by any Person respecting any matters arising hereunder.
The Sub-Servicer shall not be under any obligation to appear in, prosecute or
defend any legal action unless such action is related to its duties under this
Agreement and, unless it is specifically required to bear the costs of such
legal action or, in its opinion does not involve it in any ultimate expense or
liability; provided, however, that the Sub-Servicer may, with the consent of the
Master Servicer, undertake any such action which it may deem necessary or
desirable in respect to this Agreement and the rights and duties of the parties
hereto. In such event, the legal expenses and costs of such action and any
liability resulting therefrom shall be expenses, costs and liabilities for which
the Master Servicer will be liable and the Sub-Servicer shall be entitled to be
reimbursed therefor from the Master Servicer upon written demand.

            Section 3.04 Sub-Servicer's Resignation.

            The Sub-Servicer may resign from the obligations and duties hereby
imposed on it at any time with thirty (30) days' written notice to the Master
Servicer.

            Section 3.05 No Transfer or Assignment of Servicing.

            With respect to the responsibility of the Sub-Servicer to service
Mortgage Loans hereunder, the Sub-Servicer acknowledges that the Master Servicer
has acted in reliance upon the adequacy of the Sub-Servicer's servicing program,
its integrity, financial standing and reputation and the continuance thereof.
Without in any way limiting the generality of this Section 3.05, the parties
hereto hereby acknowledge that, except as otherwise set forth herein, any or all
of the Sub-Servicer's obligations hereunder may be performed in the
Sub-Servicer's name by CSI and that the Sub-Servicer shall neither assign nor
transfer this Agreement or the servicing hereunder nor delegate its rights or
duties hereunder or any portion thereof to any party other than CSI without the
prior written approval of the Master Servicer (which approval shall not be
unreasonably withheld or delayed).

            Section 3.06 Indemnification.

            Notwithstanding the provisions of Section 3.03, the Master Servicer
and any director, officer, agent or employee of the Master Servicer shall be
indemnified and held harmless by the Sub-Servicer against any loss, liability or
expense in connection with any legal action incurred (i) by reason of either the
Sub-Servicer's or CSI's willful misconduct, bad faith or negligence in the
performance of or reckless disregard of the Sub-Servicer's duties hereunder or
(ii) by reason of any breach by the Sub-Servicer or CSI of any representation,
warranty, covenant or agreement made by the Sub-Servicer herein.

            The Sub-Servicer and any director, officer, employee or agent of the
Sub-Servicer shall be indemnified and held harmless by the Master Servicer
against any loss, liability or expense in connection with any legal action
incurred (i) by reason of the Master Servicer's willful misconduct, bad faith or
negligence in the performance of or reckless disregard of its duties hereunder
or (ii) by reason of any breach of any representation, warranty, covenant or
agreement made by the Master Servicer herein; provided that the Master Servicer
shall have no liability to the Sub-Servicer for any action taken at the
direction of the Sub-Servicer (or for refraining, in good faith, from the taking
of any such action) in accordance with Section 3.01(c)(2). The Master Servicer
agrees to use reasonable efforts to pursue the Trust Fund for indemnification
against any loss, liability or expense incurred by a Sub-Servicer in connection
with the performance of the Sub-Servicer's duties and obligations under this
Agreement as to which the Pooling and Servicing Agreement grants to the Master
Servicer a right to indemnification from the Trust Fund, and the Sub-Servicer
shall be entitled to any such sums actually received by the Master Servicer.

            Each indemnified party hereunder shall give prompt written notice to
the indemnitor of matters which may give rise to the liability of such
indemnitor hereunder; provided, however, that failure to give such notice shall
not relieve the indemnitor of any liability except to the extent of actual
prejudice.

            This Section 3.06 shall survive the termination of this Agreement
and the termination or resignation of the Master Servicer or the Sub-Servicer.

            Section 3.07 Sub-Servicer Compensation with Respect to the Mortgage
Loans.

            The Sub-Servicer shall be entitled to a Sub-Servicing Fee with
respect to each Mortgage Loan in an amount equal to the product of (i) the
Sub-Servicing Fee Rate, on a per annum basis and (ii) the outstanding principal
balance of the related Mortgage Loan; provided, however, that any such fee shall
be payable only to the extent that collections of interest on the Mortgage Loan
is sufficient to cover the Sub-Servicing Fee to the extent that the related
Mortgage Loan is not then a Specially Serviced Mortgage Loan or a defeased Loan.

            The related Sub-Servicing Fee shall be payable on the Servicer
Remittance Date from monthly payments from the related Borrower and shall
include a report indicating (i) the then outstanding principal balance of the
related Mortgage Loan, (ii) the loan paid to date, (iii) the principal and
interest payment received by the Master Servicer on the related Mortgage Loan
and (iv) the amount of the related Sub-Servicing Fee.

                                   ARTICLE IV

                                     DEFAULT

            Section 4.01 Events of Default.

            "Event of Default," wherever used herein, unless the context
otherwise requires, means any one of the following events:

            (a) any failure on the part of the Sub-Servicer to (1) observe or
perform its obligations and duties with respect to a Mortgage Loan in strict
accordance with Section 3.01(c) of this Agreement which continue unremedied for
a period of five (5) days after the date on which notice of breach, requiring
the same to be remedied, shall be given to the Sub-Servicer by the Master
Servicer, or (2) in any way comply with Section 3.01(c)(13) through Section
3.01(c)(24) of this Agreement, provided that such failure was during the period
when the Trust Fund was subject to the reporting requirements of the Exchange
Act; or

            (b) any breach on the part of the Sub-Servicer of any representation
or warranty contained in Section 3.24(a) of the Pooling and Servicing Agreement
as modified by Section 3.01(c)(1) of this Agreement which materially and
adversely affects the interests of the Master Servicer or any Class of
Certificateholders and which continues unremedied for a period of thirty (30)
days after the date on which notice of such breach, requiring the same to be
remedied, shall have been given to the Sub-Servicer by the Master Servicer; or

            (c) an event of default with respect to the Master Servicer under
Section 7.01 of the Pooling and Servicing Agreement, which event of default
occurred as a direct result of the failure of the Sub-Servicer to perform any
obligation hereunder; or

            (d) a decree or order of a court or agency or supervisory authority
having jurisdiction in the premises in an involuntary case under any present or
future federal or state bankruptcy, insolvency or similar law for the
appointment of a conservator, receiver, liquidator, trustee or similar official
in any bankruptcy, insolvency, readjustment of debt, marshaling of assets and
liabilities or similar proceedings, or for the winding-up or liquidation of its
affairs, shall have been entered against the Sub-Servicer and such decree or
order shall have remained in force undischarged or unstayed for a period of
sixty (60) days; or

            (e) the Sub-Servicer shall consent to the appointment of a
conservator, receiver, liquidator, trustee or similar official in any
bankruptcy, insolvency, readjustment of debt, marshaling of assets and
liabilities or similar proceedings of or relating to the Sub-Servicer or of or
relating to all or substantially all of its property; or

            (f) the Sub-Servicer shall admit in writing its inability to pay its
debts generally as they become due, file a petition to take advantage of any
applicable bankruptcy, insolvency or reorganization statute, make an assignment
for the benefit of its creditors, voluntarily suspend payment of its
obligations, or take any corporate action in furtherance of the foregoing; or

            (g) the Sub-Servicer receives actual knowledge that (1) a Rating
Agency has qualified, downgraded or withdrawn its rating or ratings on one or
more Classes of Certificates, or (2) that a Rating Agency has placed one or more
Classes of Certificates on "rating watch negative" in contemplation of a rating
downgrade or withdrawal (and such "rating watch negative" placement shall not
have been withdrawn by such Rating Agency within sixty (60) days of the date the
Sub-Servicer obtained such actual knowledge), in the case of either of clauses
(1) or (2), citing servicing concerns with the Sub-Servicer or CSI as the sole
or material factor in such action; or

            (h) the Sub-Servicer shall assign or transfer or attempt to assign
or transfer all or part of its rights and obligations hereunder, except as
permitted by this Agreement.

            If any Event of Default shall occur and be continuing, then, and in
each and every such case, so long as such Event of Default shall not have been
remedied within any applicable cure period, the Master Servicer may terminate,
by notice in writing to the Sub-Servicer, all of the rights and obligations of
the Sub-Servicer as sub-servicer under this Agreement and in and to the Mortgage
Loans and the proceeds thereof. From and after the receipt by the Sub-Servicer
of such written notice, all authority and power of the Sub-Servicer under this
Agreement, whether with respect to the Mortgage Loans or otherwise, shall pass
to and be vested in the Master Servicer pursuant to and under this Section, and,
without limitation, the Master Servicer is hereby authorized and empowered to
execute and deliver, on behalf of and at the expense of the Sub-Servicer, as
attorney-in-fact or otherwise, any and all documents and other instruments, and
to do or accomplish all other acts or things necessary or appropriate to effect
the purposes of such notice of termination, whether to complete the transfer and
endorsement or assignment of the Mortgage Loans and related documents, or
otherwise. The Sub-Servicer agrees that if it is terminated pursuant to this
Section, it shall promptly (and in any event no later than five (5) Business
Days subsequent to its receipt of the notice of termination) provide the Master
Servicer with all documents and records (including, without limitation, those in
electronic form) requested by it to enable it to assume the Sub-Servicer's
functions hereunder, and shall cooperate with the Master Servicer in effecting
the termination of the Sub-Servicer's responsibilities and rights hereunder and
the assumption by a successor of the Sub-Servicer's obligations hereunder. All
accrued and unpaid Sub-Servicing Fees as of the date of termination shall be
paid to the Sub-Servicer.

            Section 4.02 Waiver of Defaults.

            The Master Servicer may waive any default by the Sub-Servicer in the
performance of its obligations hereunder and its consequences. Upon any such
waiver of a past default, such default shall cease to exist, and any Event of
Default arising therefrom shall be deemed to have been remedied for every
purpose of this Agreement. No such waiver shall extend to any subsequent or
other default or impair any right consequent thereon except to the extent
expressly so waived.

            Section 4.03 Other Remedies of Master Servicer.

            During the continuance of any Event of Default, so long as such
Event of Default shall not have been remedied, the Master Servicer, in addition
to the rights specified in Section 4.01, shall have the right, in its own name,
to take all actions now or hereafter existing at law, in equity or by statute to
enforce its rights and remedies (including the institution and prosecution of
all judicial, administrative and other proceedings and the filing of proofs of
claim and debt in connection therewith). Except as otherwise expressly provided
in this Agreement, no remedy provided for by this Agreement shall be exclusive
of any other remedy, and each and every remedy shall be cumulative and in
addition to any other remedy and no delay or omission to exercise any right or
remedy shall impair any such right or remedy or shall be deemed to be a waiver
of any Event of Default.

                                    ARTICLE V

                                   TERMINATION

            Section 5.01 Termination.

            Except as otherwise specifically set forth herein, the rights,
obligations and responsibilities of the Sub-Servicer shall terminate (without
payment of any penalty or termination fee) (i) upon the later of the final
payment or other liquidation (or any advance with respect thereto) of the last
Mortgage Loan and the disposition of all REO Property and the remittance of all
funds due hereunder; (ii) by mutual consent of the Sub-Servicer and the Master
Servicer in writing; (iii) at the option of any purchaser of the Mortgage Loans
pursuant to the Pooling and Servicing Agreement; or (iv) upon termination of the
Pooling and Servicing Agreement. Any notice of termination shall be in writing
and delivered to the Sub-Servicer as provided in Section 6.05 of this Agreement
and Sub-Servicer shall be paid all accrued and outstanding Sub-Servicing Fees as
of the date of termination.

            Section 5.02 Termination of Duties with Respect to Specially
Serviced Mortgage Loans.

            At such time as any of the Mortgage Loans becomes a Specially
Serviced Mortgage Loan, the obligations and duties of the Sub-Servicer set forth
herein with respect to such Specially Serviced Mortgage Loan that are required
to be performed by the Special Servicer under the Pooling and Servicing
Agreement shall cease; provided, however, that although duties of the
Sub-Servicer shall terminate to the extent transferred to the Special Servicer,
the Sub-Servicer shall retain the Mortgage Loan on its computer system so long
as the Mortgage Loan is a Specially Serviced Mortgage Loan. If a Mortgage Loan
is retained on the computer systems of the Sub-Servicer, the Mortgage Loan shall
be subject to the rights of the Special Servicer while the Mortgage Loan is a
Specially Serviced Mortgage Loan. In addition, the Sub-Servicer shall continue
to perform all of its duties hereunder with respect to a Specially Serviced
Mortgage Loan that are not required to be performed by the Special Servicer
pursuant to the Pooling and Servicing Agreement. If a Specially Serviced
Mortgage Loan becomes a Corrected Mortgage Loan, the Sub-Servicer shall commence
servicing such Corrected Mortgage Loan pursuant to the terms of this Agreement.

                                   ARTICLE VI

                                  MISCELLANEOUS

            Section 6.01 Successor to the Sub-Servicer.

            Prior to termination of the Sub-Servicer's responsibilities and
duties under this Agreement pursuant to Section 3.04, 4.01 or 5.01 of this
Agreement, the Master Servicer shall (i) succeed to and assume all of the
Sub-Servicer's responsibilities, rights, duties and obligations under this
Agreement, or (ii) appoint a successor which satisfies the criteria for a
successor Sub-Servicer in Section 3.02 of this Agreement and which shall succeed
to all rights and assume all of the responsibilities, duties and liabilities of
the Sub-Servicer under this Agreement accruing following the termination of the
Sub-Servicer's responsibilities, duties and liabilities under this Agreement.

            Section 6.02 Financial Statements.

            The Sub-Servicer shall, upon request, deliver to the Master Servicer
its most recent financial statements and, upon the request of the Master
Servicer, make available such other records relevant to the performance of the
Sub-Servicer's obligations hereunder as may be reasonably requested by the
Master Servicer to the extent required to enable the Master Servicer to fulfill
its related obligations under the Pooling and Servicing Agreement.

            Section 6.03 Closing.

            The closing for the commencement of the Sub-Servicer to perform the
servicing responsibilities under this Agreement with respect to the Mortgage
Loans shall take place on the Closing Date. At the Master Servicer's option, the
closing shall be either by telephone, confirmed by letter or wire as the parties
shall agree, or conducted in person, at such place as the parties shall agree.

            The closing shall be subject to the execution and delivery of the
Pooling and Servicing Agreement by the parties thereto.

            Section 6.04 Closing Documents.

            The Closing Documents shall consist of all of the following
documents:

            (a)   to be provided by the Sub-Servicer and CSI:

                  (1) this Agreement executed by the Sub-Servicer and
            acknowledged by CSI;

                  (2) a Secretary's Certificate of the Sub-Servicer and a
            Secretary's Certificate of CSI, in each case dated the Closing Date
            and substantially in the form of Exhibit C hereto, including all
            attachments thereto; and

            (b)   to be provided by the Master Servicer:

                  (1) this Agreement executed by the Master Servicer;

                  (2) the Mortgage Loan Schedule, with one copy to be attached
            to each counterpart of this Agreement as Exhibit A hereto; and

                  (3) the Pooling and Servicing Agreement substantially in the
            form of Exhibit D hereto.

            Section 6.05 Notices.

            All demands, notices, consents and communications hereunder shall be
in writing and shall be deemed to have been duly given when delivered to the
following addresses:

            (i) if to the Master Servicer:

            Wachovia Bank, National Association
            8739 Research Drive URP4
            Charlotte, North Carolina 28262
            Attention: Credit Suisse First Boston
            Mortgage Securities Corp., Commercial Mortgage
            Pass-Through Certificates, Series 2007-C4
            Telecopy No.: (704) 715-0036

            with copies to:

            Lar Carlsten, Esq.
            c/o Wachovia Bank Corporation
            301 S. College St. TW-30
            Charlotte, NC 28288-0630
            Re: Credit Suisse First Boston Mortgage Securities Corp.,
            Commercial Mortgage Pass-Through Certificates, Series 2007-C4

            and

            (ii) if to the Sub-Servicer:

            Column Financial, Inc.
            11 Madison Avenue
            5th Floor
            New York, New York 10010
            Attention: Larry Goland
            Attention: George Winckler

            and

            Column Financial, Inc.
            3414 Peachtree Road N.E.
            Suite 1140
            Atlanta, Georgia 30326
            Attention: Bob Barnes

            with copies to:

            Casey McCutcheon, Esq.
            Legal & Compliance Department
            Telecopy No.: (917) 326-8433

            and

            Cadwalader, Wickersham & Taft LLP
            One World Financial Center
            New York, New York  10281
            Attention: Patrick T. Quinn

            and

            (iii) if to CSI:

            Centerline Servicing Inc.
            5221 N. O'Connor Blvd.
            Suite 600
            Irving, Texas 75039
            Attention: John Lloyd

            with a copy to:

            Centerline Servicing Inc.
            5221 N. O'Connor Blvd.
            Suite 600
            Irving, Texas 75039
            Attention: Jenna Unell

or such other address as may hereafter be furnished to the other party by
like notice.

            Section 6.06 Severability Clause.

            Any part, provision, representation or warranty of this Agreement
which is prohibited or which is held to be void or unenforceable shall be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction as to the Mortgage Loans shall not
invalidate or render unenforceable such provision in any other jurisdiction. If
the invalidity of any part, provision, representation or warranty of this
Agreement shall deprive any party of the economic benefit intended to be
conferred by this Agreement, the parties shall negotiate, in good faith, to
develop a structure the economic effect of which is nearly as possible the same
as the economic effect of this Agreement without regard to such invalidity.

            Section 6.07 Counterparts.

            This Agreement may be executed simultaneously in any number of
counterparts. Each counterpart shall be deemed to be an original, and all such
counterparts shall constitute one and the same instrument.

            Section 6.08 Governing Law.

            In order to, among other things, conform to the governing law
provision of the Pooling and Servicing Agreement, this Agreement shall be
construed in accordance with the laws of the State of New York and the
obligations, rights and remedies of the parties hereunder shall be determined in
accordance with the laws of the State of New York, except to the extent
preempted by federal law.

            Section 6.09 Protection of Confidential Information.

            The Sub-Servicer shall keep confidential and shall not divulge to
any party other than CSI, the Master Servicer, the Depositor, the Special
Servicer or the Trustee, without the Master Servicer's prior written consent,
any information pertaining to the Mortgage Loans or any borrower thereunder,
except to the extent that it is appropriate for the Sub-Servicer to do so in
working with third-party vendors, property inspectors, legal counsel, auditors,
taxing authorities or other governmental agencies or in accordance with this
Agreement.

            Section 6.10 Intention of the Parties.

            It is the intention of the parties that the Master Servicer is
conveying, and the Sub-Servicer is receiving, only a contract for servicing the
Mortgage Loans. Accordingly, the parties hereby acknowledge that the Trustee
remains the sole and absolute beneficial owner of the Mortgage Loans and all
rights related thereto.

            Section 6.11 Third Party Beneficiary.

            Each of the Depositor and the Trustee, for the benefit of the
Certificateholders, shall be a third party beneficiary under this Agreement;
provided that, except to the extent the Trustee or its designee assumes the
obligations of the Master Servicer hereunder as contemplated by Section 6.12 of
this Agreement, none of the Depositor, the Trustee, the Trust Fund, any
successor Master Servicer, or any Certificateholder shall have any duties under
this Agreement or any liabilities arising herefrom.

            Section 6.12 Successors and Assigns; Assignment of Agreement.

            This Agreement shall bind and inure to the benefit of and be
enforceable by the Sub-Servicer and the Master Servicer and the respective
successors and assigns of the Sub-Servicer and the Master Servicer. This
Agreement shall not be assigned, pledged or hypothecated by the Sub-Servicer to
a third party except as otherwise specifically provided for herein. If the
Master Servicer shall for any reason no longer act in such capacity under the
Pooling and Servicing Agreement, the Trustee or its designee may thereupon
assume all of the rights and, except to the extent they arose prior to the date
of assumption, obligations of the Master Servicer under this Agreement.

            Section 6.13 Waivers.

            No term or provision of this Agreement may be waived or modified
unless such waiver or modification is in writing and signed by the party against
whom such waiver or modification is sought to be enforced.

            Section 6.14 Exhibits.

            The exhibits to this Agreement are hereby incorporated and made a
part hereof and are an integral part of this Agreement.

            Section 6.15 General Interpretive Principles.

            The article and section headings are for convenience of a reference
only, and shall not limit or otherwise affect the meaning hereof.

            Section 6.16 Complete Agreement.

            This Agreement embodies the complete agreement between the parties
regarding the subject matter hereof and may not be varied except by a written
agreement conforming to the provisions of Section 6.18 of this Agreement. All
prior negotiations or representations of the parties are merged into this
Agreement and shall have no force or effect unless expressly stated herein.

            Section 6.17 Further Agreement.

            The Sub-Servicer and the Master Servicer each agree to execute and
deliver to the other such reasonable and appropriate additional documents,
instruments or agreements as may be necessary or appropriate to effectuate the
purposes of this Agreement.

            Section 6.18 Amendments.

            This Agreement may only be amended with the consent of the
Sub-Servicer and the Master Servicer. No amendment to the Pooling and Servicing
Agreement that purports to change the rights or obligations of the Sub-Servicer
hereunder shall be effective against the Sub-Servicer without the express
written consent of the Sub-Servicer.

                   [SIGNATURES COMMENCE ON THE FOLLOWING PAGE]

<PAGE>

            IN WITNESS WHEREOF, the Sub-Servicer and the Master Servicer have
caused their names to be signed hereto by their respective officers thereunto
duly authorized as of the date first above written.

                                          COLUMN FINANCIAL, INC.



                                          By: /s/ Jeffrey A. Altabef
                                          -------------------------------------
                                          Name: Jeffrey A. Altabef
                                          Title: Vice President


                                          WACHOVIA BANK, NATIONAL ASSOCIATION,
                                             Master Servicer,



                                          By: /s/ Scott R. Rossbach
                                          -------------------------------------
                                          Name: Scott R. Rossbach
                                          Title: Vice President


Acknowledged and agreed:

CENTERLINE SERVICING INC.



By: /s/ John Lloyd
   ----------------------------
   Name: John Lloyd
   Title: Director

<PAGE>

                                    EXHIBIT A

                             MORTGAGE LOAN SCHEDULE

                                                               SUB-SERVICING FEE
                                                                  RATE
 LOAN #       PROPERTY NAME             CUT-OFF BALANCE         (BASIS POINTS)
--------------------------------------------------------------------------------
   11    Sweetwater Crossings           $29,000,000.00               0.00
   76    Drug Mart Plaza A - ROLLUP      $5,775,000.00               0.00

<PAGE>

                                    EXHIBIT B

                 MASTER SERVICER REPRESENTATIONS AND WARRANTIES

      (1) The Master Servicer is a national banking association duly organized,
validly existing and in good standing under the laws of the United States, and
the Master Servicer is in compliance with the laws of each State in which any
Mortgaged Property is located to the extent necessary to perform its obligations
under this Agreement, except where the failure to so qualify or comply would not
have a material adverse effect on the ability of the Master Servicer to perform
its obligations hereunder;

      (2) The execution and delivery of this Agreement by the Master Servicer,
and the performance and compliance with the terms of this Agreement by the
Master Servicer, will not (A) violate the Master Servicer's certificate of
incorporation or charter and by-laws or other comparable organizational
documents or (B) constitute a default (or an event which, with notice or lapse
of time, or both, would constitute a default) under, or result in the breach of,
any material agreement or other material instrument to which it is a party or
which is applicable to it or any of its assets, or (C) result in the violation
of any law, rule, regulation, order, judgment or decree binding on the Master
Servicer which, in the case of either (B) or (C), is likely to materially and
adversely affect the Master Servicer's ability to perform hereunder;

      (3) This Agreement, assuming due authorization, execution and delivery by
the other parties hereto, constitutes a valid, legal and binding obligation of
the Master Servicer, enforceable against the Master Servicer in accordance with
the terms hereof, except as such enforcement may be limited by (A) applicable
bankruptcy, insolvency, reorganization, liquidation, receivership, moratorium
and other laws relating to or affecting creditors' rights generally, and (B)
general principles of equity, regardless of whether such enforcement is
considered in a proceeding in equity or at law;

      (4) The Master Servicer is not in violation with respect to any law, any
order or decree of any court, or any order, regulation or demand of any federal,
state, municipal or governmental agency, which violations are reasonably likely
to have consequences that would materially and adversely affect (A) the
financial condition or operations of the Master Servicer or its properties taken
as a whole or (B) its ability to perform its duties and obligations hereunder;

      (5) No litigation is pending or, to the best of the Master Servicer's
knowledge, threatened against the Master Servicer which, if determined adversely
to the Master Servicer, would prohibit the Master Servicer from entering into
this Agreement or, in the Master Servicer's reasonable judgment, is likely to
materially and adversely affect the ability of the Master Servicer to perform
its obligations under this Agreement;

      (6) No consent, approval, authorization or order of any court or
governmental agency or body is required for the execution, delivery and
performance by such Master Servicer of, or compliance by the Master Servicer
with, this Agreement or the consummation of the Master Servicer's transactions
contemplated by this Agreement, except for any consent, approval, authorization
or order which has been obtained or cannot be obtained prior to the actual
performance by the Master Servicer of its obligations under this Agreement, or
which, if not obtained, would not have a materially adverse effect on the
ability of the Master Servicer to perform its obligations hereunder;

      (7) The Master Servicer has full corporate power and authority to enter
into and perform in accordance with this Agreement, has duly authorized the
execution, delivery and performance of this Agreement, and has duly executed and
delivered this Agreement; and

      (8) Each officer and employee of the Master Servicer that has
responsibilities concerning the servicing and administration of Mortgage Loans
is covered by errors and omissions insurance and the fidelity bond in the
amounts and with the coverage required by Section 3.07(c) of the Pooling and
Servicing Agreement.

<PAGE>

                                    EXHIBIT C

                         FORM OF SECRETARY'S CERTIFICATE

            I, ______________________________, hereby certify that I am the duly
elected __________________________ of [Column Financial, Inc.][Centerline
Servicing Inc.] (the "Sub-Servicer"), a corporation organized under the laws of
Delaware and further as follows:

            1.    Attached hereto as Exhibit A is a full, true and accurate copy
                  of the Sub-Servicer's Certificate of Incorporation. The
                  Certificate of Incorporation is in full force and effect as of
                  the date hereof and, to the best of my knowledge no action has
                  been taken or contemplated looking toward any such amendment.

            2.    Attached hereto as Exhibit B is a full, true and accurate copy
                  of the By-laws of the Sub-Servicer as in effect on
                  _______________, and at all times subsequent thereto.

            3.    Attached hereto as Exhibit 3 is an original certificate of
                  good standing of the Sub-Servicer, dated as of _____, 200__,
                  and no event has occurred since the date thereof which would
                  impair such standing.

            4.    Attached hereto as Exhibit 4 is a true, correct and complete
                  copy of the Resolution adopted by the Board of Directors of
                  the Sub-Servicer authorizing the Sub-Servicer to execute and
                  deliver, among other documents, the Sub-Servicing Agreement,
                  dated as of _________, 200__ (the "Sub-Servicing Agreement"),
                  by and between the Sub-Servicer and Wachovia Bank, National
                  Association, and such resolutions are in effect on the date
                  hereof and have been in effect without amendment, waiver,
                  rescission or modification since _______________.

            5.    Each person listed on Exhibit 5 attached hereto who, as an
                  officer or representative of the Sub-Servicer, signed the
                  Sub-Servicing Agreement and any other document delivered prior
                  hereto or on the date hereof in connection with the
                  Sub-Servicing Agreement, was, at the respective times of such
                  signing and delivery, and is now, a duly elected or appointed,
                  qualified and acting officer or representative of the
                  Sub-Servicer, who holds the office set forth opposite his or
                  her name on Exhibit 5, and the signatures of such persons
                  appearing on such documents are their genuine signatures.


<PAGE>

            IN WITNESS WHEREOF, I have hereunto signed my name.

Dated: _____________________________     By: ________________________________
                                             Name:
                                             Title: [Assistant] Secretary


<PAGE>

                                    EXHIBIT 5
                                       to
                     Sub-Servicer's Secretary's Certificate

           Name                       Title                    Signature
           ----                       -----                    ---------



<PAGE>

                                    EXHIBIT D

                         POOLING AND SERVICING AGREEMENT

                                 See Exhibit 4.1