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                                                                   Exhibit 10.52

                              AMENDMENT NUMBER SIX
                                     to the
                         AMENDED AND RESTATED INDENTURE,
                         dated as of November 25, 2003,
                                     between
                       OPTION ONE OWNER TRUST 2001-1A and
                             WELLS FARGO BANK, N.A.

            This AMENDMENT NUMBER SIX (this "Amendment") is made and is
effective as of this 29th day of April, 2005, between Option One Owner Trust
2001-1A (the "Issuer") and Wells Fargo Bank, N.A., as Indenture Trustee (the
"Indenture Trustee"), to the Amended and Restated Indenture, dated as of
November 25, 2003 (the "Indenture"), between the Issuer and the Indenture
Trustee.

                                    RECITALS

            WHEREAS, the parties hereto desire to amend the Indenture subject to
the terms and conditions of this Amendment.

            NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, and of the mutual covenants herein
contained, the parties hereto hereby agree as follows:

            SECTION 1. Defined Terms. Any terms capitalized but not otherwise
defined herein shall have the respective meanings set forth in the Indenture.

            SECTION 2. Amendment. Effective as of April 29, 2005, Section 1.01
of the Indenture is hereby amended by deleting in its entirety the definition of
"Maturity Date" and replacing it with the following:

            "Maturity Date" means, with respect to the Notes, April 28, 2006.

            SECTION 3. Representations. In order to induce the parties hereto to
execute and deliver this Amendment, the Issuer hereby represents to the
Indenture Trustee and the Noteholders that as of the date hereof, after giving
effect to this Amendment, (a) all of its respective representations and
warranties in the Indenture and the other Basic Documents are true and correct,
and (b) it is otherwise in full compliance with all of the terms and conditions
of the Indenture and the other Basic Documents.

            SECTION 4. Limited Effect. Except as expressly amended and modified
by this Amendment, the Indenture shall continue in full force and effect in
accordance with its terms. Reference to this Amendment need not be made in the
Indenture or any other instrument or

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document executed in connection therewith or herewith, or in any certificate,
letter or communication issued or made pursuant to, or with respect to, the
Indenture, any reference in any of such items to the Indenture being sufficient
to refer to the Indenture as amended hereby.

            SECTION 5. Fees and Expenses. The Issuer covenants to pay as and
when billed by the Initial Noteholder all of the reasonable out-of-pocket costs
and expenses incurred in connection with the transactions contemplated hereby
and in the other Basic Documents including, without limitation, (i) all
reasonable fees, disbursements and expenses of counsel to the Initial Noteholder
and (ii) all reasonable fees and expenses of the Indenture Trustee and its
counsel.

            SECTION 6. Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD
TO THE CONFLICT OF LAWS DOCTRINE APPLIED IN SUCH STATE.

            SECTION 7. 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 8. Limitation on Liability. It is expressly understood and
agreed by the parties hereto that (a) this Amendment is executed and delivered
by Wilmington Trust Company, not individually or personally, but solely as Owner
Trustee of Option One Owner Trust 2001-1A in the exercise of the powers and
authority conferred and vested in it, (b) each of the representations,
undertakings and agreements herein made on the part of the Issuer is made and
intended not as personal representations, undertakings and agreements by
Wilmington Trust Company but is made and intended for the purpose for binding
only the Issuer, (c) nothing herein contained shall be construed as creating any
liability on Wilmington Trust Company, individually or personally, to perform
any covenant either expressed or implied contained herein, all such liability,
if any, being expressly waived by the parties hereto and by any Person claiming
by, through or under the parties hereto and (d) under no circumstances shall
Wilmington Trust Company be personally liable for the payment of any
indebtedness or expenses of the Issuer or be liable for the breach or failure of
any obligation, representation, warranty or covenant made or undertaken by the
Issuer under this Amendment or any other related documents.

                            [signature page follows]

                                       2
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            IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be executed and delivered by their duly authorized officers as of the day and
year first above written.

                                 OPTION ONE OWNER TRUST 2001-1A

                                 By: Wilmington Trust Company, not in its
                                 individual capacity but solely as owner trustee

                                 By: /s/ Mary K Pupillo
                                     -------------------------------------------
                                 Name: Mary K. Pupillo
                                 Title: Assistant Vice President

                                 WELLS FARGO BANK, N.A., as Indenture Trustee

                                 By: Darron C. Woodus
                                 Name: Darron C. Woodus
                                 Title: Assistant Vice President