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                                                                    EXHIBIT 4.1a


                        SUPPLEMENT NO. 1 TO THE INDENTURE

                             dated as of _____, 2002

                                     between

                    SPECIALTY MORTGAGE TRUST, INC., as Issuer

                                       and

                      DEUTSCHE BANK NATIONAL TRUST COMPANY,
          formerly known as Bankers Trust Company of California, N.A.,
                                   as Trustee


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            SUPPLEMENT NO. 1 TO THE INDENTURE dated as of _____, 2002
("Supplemental Indenture") between SPECIALTY MORTGAGE TRUST, INC. (the
"Issuer"), and DEUTSCHE BANK NATIONAL TRUST COMPANY, formerly known as Bankers
Trust Company of California, N.A., a national banking association, as trustee
(the "Trustee"), to the Indenture dated as of January 1, 2001, by and between
the Issuer and the Trustee (the "Indenture").

            WHEREAS, Section 9.01 of the Indenture permits entry into agreements
supplemental to the Indenture upon the terms and conditions specified therein;

            WHEREAS, the Issuer and the Trustee have heretofore executed the
Indenture;

            WHEREAS, the Issuer and the Trustee wish to amend certain terms of
the Indenture by entering into this Supplemental Indenture; and

            WHEREAS, such action will not adversely affect the interests of the
Holders of the Notes.

            NOW, THEREFORE, the Issuer and the Trustee agree to enter into this
Supplemental Indenture, hereby supplementing certain terms of the Indenture, as
of the date hereof as follows:

        Section 1. Definitions. Each term used but not defined herein shall have
the meaning assigned to such term in the Indenture.

        Section 2. Amendments.

        A. Clause (b) of Section 2.03 of the Indenture is amended to read:

                "The Notes will mature a minimum of one month and a maximum of
        five years from the date of issuance, as stated on the face of each Note
        (the "Stated Maturity"). The principal of each Note shall be payable at
        the Stated Maturity thereof unless the unpaid principal of such Note
        becomes due and payable at an earlier date by declaration of
        acceleration or otherwise. All cash payments made with respect to any
        Note shall be applied first to the interest then due and payable on such
        Note and then to the principal thereof."

        B. The second to last sentence of the first paragraph of Clause (c) of
Section 2.03 of the Indenture is amended to read:

                "The interest rate on the Notes will in no event be less than
        the applicable federal rate (as defined in Section 1274(d) of the Code)
        as periodically set by the Internal Revenue Service for the
        corresponding term to maturity."

        C. The last sentence of the first paragraph of Clause (c) of Section
2.03 of the Indenture is amended to read:

                "Interest is payable to the persons in whose names the Notes are
        registered at the election of the Noteholder either (a) payable monthly
        in arrears, on the Payment Date of each month or such other day as may
        be provided in the related Issuer Order or (b) compounded monthly and
        payable at the earlier of the Stated Maturity or the annual anniversary
        of issuance."

        D. Clause (a) of Section 3.12 of the Indenture is amended to read:

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                "The ratio of (a) the Total Indebtedness of the Issuer, both
        secured and unsecured, to (b) the GAAP Net Worth of the Issuer, is
        limited to no more than 4:1."

        E. The first sentence of Section 3.13 of the Indenture is amended to
read:

                "The Issuer will withhold 31% (or other required back-up
        withholding tax rate then in effect) of any interest payable to any
        Holder who has not provided a fully executed Form W-9 or satisfactory
        equivalent or where the Internal Revenue Service has notified the Issuer
        that back-up withholding is otherwise required."

        Section 3. Counterparts. This Supplemental Indenture may be executed in
several counterparts, each of which shall be deemed an original hereof and all
of which, when taken together, shall constitute one and the same Supplemental
Indenture.

        Section 4. Ratification of Indenture. Except as provided herein, all
provisions, terms and conditions of the Indenture shall remain in full force and
effect. This Supplemental Indenture is not intended to, and shall not, modify,
add to, or amend any of the terms of the Notes, including, but not limited to,
the Stated Maturity of the Notes, that were issued under the Indenture prior to
the date of this Supplemental Indenture. As supplemented by this Supplemental
Indenture, the Indenture is ratified and confirmed in all respects.

        Section 5. Entire Agreement. This Supplemental Indenture sets forth the
entire agreement between the Issuer and the Trustee with respect to the subject
matter hereof, and this Supplemental Indenture supersedes and replaces any
agreement or understanding that may have existed between the Issuer and the
Trustee prior to the date hereof in respect of such subject matter.

            IN WITNESS WHEREOF, the parties hereto have executed this
Supplemental Indenture as of the date set forth above.

                                    SPECIALTY MORTGAGE TRUST, INC., as Issuer


                                    By:
                                         ---------------------------------------
                                         Name:
                                         Title:


                                    DEUTSCHE BANK NATIONAL TRUST COMPANY,
                                      formerly known as Bankers Trust Company
                                      of California, N.A., as Trustee


                                    By:
                                         ---------------------------------------
                                         Name:
                                         Title: