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                                                                   EXHIBIT 10.10

                                                               EXECUTION VERSION

                                 AMENDMENT NO. 4

                         TO MASTER REPURCHASE AGREEMENT

                  Amendment No. 4, dated as of December 16, 2002 (this
"Amendment"), between CREDIT SUISSE FIRST BOSTON MORTGAGE CAPITAL LLC (the
"Buyer") and OAK STREET MORTGAGE LLC (formerly known as Cresleigh Financial
Services LLC (the "Seller").

                                    RECITALS

                  The Buyer and the Seller are parties to that certain Master
Repurchase Agreement, dated as of March 1, 2002, as amended by Amendment No. 1,
dated as of May 30, 2002, Amendment No. 2, dated as of September 29, 2002 and
Amendment No. 3, dated as of October 30, 2002 (the "Existing Repurchase
Agreement"; as amended by this Amendment, the "Repurchase Agreement").
Capitalized terms used but not otherwise defined herein shall have the meanings
given to them in the Existing Repurchase Agreement.

                  The Buyer and the Seller have agreed, subject to the terms and
conditions of this Amendment, that the Existing Repurchase Agreement be amended
to reflect certain agreed upon revisions to the terms of the Existing Repurchase
Agreement.

                  Accordingly, the Buyer and the Seller hereby agree, in
consideration of the mutual premises and mutual obligations set forth herein,
that the Existing Repurchase Agreement is hereby amended as follows:

                  SECTION 1. Agreement. Notwithstanding anything to the contrary
set forth in Amendment No. 2 to the Existing Repurchase Agreement, all
references to the "Due Diligence Holdback Account" and "Due Diligence Holdback
Amount", including the definitions thereof, all conditions precedent,
representations and warranties, and covenants related thereto shall remain in
full force and effect with respect to Increased Purchase Price Mortgage Loans
during the Increased Maximum Aggregate Cash Purchase Period (as defined below).

                  SECTION 2. Increased Maximum Aggregate Cash Purchase Price
Period. For purposes of this Amendment, this Section 1 will be effective only
during the Increased Maximum Aggregate Cash Purchase Price Period.

                  (a) Section 2 of the Existing Repurchase Agreement is hereby
temporarily amended by adding the following defined terms, which amendment shall
be effective solely during the Increased Maximum Aggregate Cash Purchase Price
Period (as defined below):

                  "Increased Aggregate Cash Purchase Price" means TWENTY FIVE
MILLION DOLLARS ($25,000,000).

                  "Increased Maximum Aggregate Cash Purchase Price Period" shall
mean the period beginning on the date hereof through and including January 31,
2003."



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                  "Increased Cash Purchase Price Mortgage Loans" means a
Mortgage Loan which is purchased with the proceeds of the Increased Aggregate
Cash Purchase Price. Any Mortgage Loans subject to a Transaction will first be
attributed to the Standard Aggregate Cash Purchase Price prior to any Mortgage
Loans being attributed to the Increased Aggregate Cash Purchase Price. To the
extent that funds are no longer available under the Standard Aggregate Cash
Purchase Price, any further Mortgage Loans subject to a Transaction will be
considered Increased Cash Purchase Price Mortgage Loans. For purposes of this
Agreement, Mortgage Loans will be allocated first to the Standard Aggregate Cash
Purchase Price based on the date on which such Mortgage Loan becomes subject to
this Agreement, commencing from the earliest date to the most recent date.

                  "Standard Aggregate Cash Purchase Price" means SEVENTY FIVE
MILLION DOLLARS ($75,000,000).

                  (b) Section 2 of the Existing Repurchase Agreement is hereby
temporarily amended by deleting the definition of "Cash Purchase Price
Percentage" in its entirety and replacing it with the following language, which
amendment shall be effective solely during the Increased Maximum Aggregate Cash
Purchase Price Period:

                  "Cash Purchase Price Percentage" means

                  (i) with respect to each Increased Cash Purchase Price
Mortgage Loan, 92%; and

                  (ii) with respect to each Mortgage Loan (other than an
Increased Cash Purchase Price Mortgage Loan), the following percentage, as
applicable:

                           (a) 97% with respect to Purchased Mortgage Loans that
                  are Sub-Prime Mortgage Loans;

                           (b) 98% with respect to Purchased Mortgage Loans that
                  are Alt A Mortgage Loans;

                           (c) 98% with respect to Purchased Mortgage Loans that
                  are Jumbo Mortgage Loans;

                           (d) 98% with respect to Purchased Mortgage Loans that
                  are first lien Conforming Mortgage Loans;

                           (e) 95% with respect to Purchased Mortgage Loans that
                  are Second Lien Mortgage Loans; and

                  (iii) with respect to Transactions the subject of which are
Exception Mortgage Loans, a percentage to be determined by Buyer in its sole
discretion.

                  (c)      Section 2 of the Existing Repurchase Agreement is
         hereby temporarily amended by deleting the definition of "Market Value"
         in its entirety and replacing it with the following language, which
         amendment shall be effective solely during the Increased Maximum
         Aggregate Cash Purchase Price Period:

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                  "Market Value" means, with respect to any Purchased Mortgage
Loan as of any date of determination, the whole loan servicing released fair
market value of such Purchased Mortgage Loan on such date as determined by Buyer
(or an Affiliate thereof) in its sole discretion. Without limiting the
generality of the foregoing, Seller acknowledges that the Market Value of a
Purchased Mortgage Loan may be reduced to zero by Buyer (and, to the extent that
such reduction causes a Margin Call pursuant to Section 6(a), such reduction
shall be communicated to Seller) if:

                           (i)      a material breach of a representation,
                  warranty or covenant made by Seller in this Agreement with
                  respect to such Purchased Mortgage Loan which adversely
                  affects its collectibility or Market Value has occurred and is
                  continuing;

                           (ii)     such Purchased Mortgage Loan is a
                  Non-Performing Mortgage Loan;

                           (iii)    such Purchased Mortgage Loan has been
                  released from the possession of the Custodian under the
                  Custodial Agreement (other than to a Take-out Investor
                  pursuant to a Bailee Letter) for a period in excess of ten
                  (10) calendar days;

                           (iv)     such Purchased Mortgage Loan has been
                  released from the possession of the Custodian under the
                  Custodial Agreement to a Take-out Investor pursuant to a
                  Bailee Letter for a period in excess of 45 calendar days;

                           (v)      such Purchased Mortgage Loan has been
                  subject to a Transaction hereunder for a period of greater
                  than 90 days; (vi) such Purchased Mortgage Loan is a Wet-Ink
                  Mortgage Loan, for which the Mortgage File has not been
                  delivered to the Custodian on or prior to the seventh Business
                  Day after the related Purchase Date;

                           (vii)    when the Mortgage Loan is a Second Lien
                  Mortgage Loan and the Cash Purchase Price for such Purchased
                  Mortgage Loan is added to other Purchased Mortgage Loans, the
                  aggregate Cash Purchase Price of all Second Lien Mortgage
                  Loans that are Purchased Mortgage Loans exceeds $7.5 million;

                           (viii)   when the Mortgage Loan is a Sub-Prime
                  Mortgage Loan and the Cash Purchase Price for such Purchased
                  Mortgage Loan is added to other Purchased Mortgage Loans, the
                  aggregate Cash Purchase Price of all Sub-Prime Mortgage Loans
                  that are Purchased Mortgage Loans exceeds $60 million; or

                           (ix)     during the first five (5) Business Days and
                  the last three (3) Business Days of each calendar month, when
                  the Mortgage Loan is a Wet-Ink Mortgage Loan and the Cash
                  Purchase Price for such Purchased Mortgage Loan is added to
                  other Purchased Mortgage Loans, the aggregate Cash Purchase
                  Price of all Wet-Ink Mortgage Loans that are Purchased
                  Mortgage Loans exceeds 40% of the Maximum Aggregate Cash
                  Purchase Price.

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                           (x)      other than during the first five (5)
                  Business Days and the last three (3) Business Days of each
                  calendar month, when the Mortgage Loan is a Wet-Ink Mortgage
                  Loan and the Cash Purchase Price for such Purchased Mortgage
                  Loan is added to other Purchased Mortgage Loans, the aggregate
                  Cash Purchase Price of all Wet-Ink Mortgage Loans that are
                  Purchased Mortgage Loans exceeds 30% of the Maximum Aggregate
                  Cash Purchase Price.

                  (b) Section 2 of the Existing Repurchase Agreement is hereby
         temporarily amended by deleting the definition of "Maximum Aggregate
         Cash Purchase Price" in its entirety and replacing it with the
         following language, which amendment shall be effective solely during
         the Increased Maximum Aggregate Cash Purchase Price Period:

                  "Maximum Aggregate Cash Purchase Price" means the sum of (a)
the Standard Aggregate Cash Purchase Price plus (b) the Increased Aggregate Cash
Purchase Price. All funds made available by Buyer to Seller under this Agreement
will first be attributed to the Standard Aggregate Cash Purchase Price."

                  SECTION 3. Conditions Precedent. This Amendment shall become
effective on December 16, 2002 (the "Amendment Effective Date"), subject to the
satisfaction of the following conditions precedent:

                  3.1 Delivered Documents. On the Amendment Effective Date, the
Buyer shall have received the following documents, each of which shall be
satisfactory to the Buyer in form and substance:

                  (a) this Amendment, executed and delivered by a duly
         authorized officer of the Buyer and the Seller;

                  (b) such other documents as the Buyer or counsel to the Buyer
         may reasonably request.

                  SECTION 4. Representations and Warranties. The Seller hereby
represents and warrants to the Buyer that it is in compliance with all the terms
and provisions set forth in the Repurchase Agreement on its part to be observed
or performed, and that no Event of Default has occurred or is continuing, and
hereby confirm and reaffirm the representations and warranties contained in
Section 13 of the Repurchase Agreement.

                  SECTION 5. Limited Effect. Except as expressly amended and
modified by this Amendment, the Existing Repurchase Agreement shall continue to
be, and shall remain, in full force and effect in accordance with its terms.

                  SECTION 6. Counterparts. This Amendment may be executed by
each of the parties hereto on any number of separate counterparts, each of which
shall be an original and all of which taken together shall constitute one and
the same instrument.

                  SECTION 7. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY,
AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE

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STATE OF NEW YORK WITHOUT REFERENCE TO THE CHOICE OF LAW PROVISIONS THEREOF.

                            [SIGNATURE PAGE FOLLOWS]

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                  IN WITNESS WHEREOF, the parties have caused their names to be
signed hereto by their respective officers thereunto duly authorized as of the
day and year first above written.

Buyer:

                                CREDIT SUISSE FIRST BOSTON MORTGAGE CAPITAL LLC,
                                as Buyer

                                By: /s/ Jeffrey A. Detwiler
                                    --------------------------------------------
                                    Name: Jeffrey A. Detwiler
                                    Title: Managing Director

Seller:

                                OAK STREET MORTGAGE LLC
                                as Seller

                                By: /s/ Craig L. Royal
                                    --------------------------------------------
                                    Name: Craig L. Royal
                                    Title: Chief Financial Officer