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                                                                    EXHIBIT 10.6

                                                                  Execution Copy

                                 AMENDMENT NO. 4
           TO AMENDED AND RESTATED MASTER LOAN AND SECURITY AGREEMENT

     This AMENDMENT NO. 4 is dated as of August 15, 2002 (this "Amendment"),
and amends the Amended and Restated Master Loan and Security Agreement, dated as
of December 1, 2001, as amended (the "Loan and Security Agreement"), and is
between NC Capital Corporation and Morgan Stanley Dean Witter Mortgage Capital
Inc.

                                   WITNESSETH:

     WHEREAS, the parties hereto desire to make a certain amendment to the
Loan and Security Agreement as hereinafter set forth; and

     WHEREAS, pursuant to Section 11.4 of the Loan and Security Agreement, the
parties hereto are permitted to amend the Loan and Security Agreement:

     NOW THEREFORE, in consideration of the above recitals and for other good
and valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the parties hereto agree as follows:

     SECTION 1.  Definitions. Capitalized terms used herein but not defined
shall have the meanings set forth in the Loan and Security Agreement.

     SECTION 2.  Amendment. The Loan and Security Agreement is hereby amended as
set forth below:

          The definition of the term "Maximum Credit" is hereby amended in its
     entirety to read as follows:

          "Maximum Credit" shall mean $500,000,000.00, as reduced in accordance
     with Section 2.1 hereof.

     SECTION 3.  Survival. Except as expressly amended hereby, the Loan and
Security Agreement shall continue in full force and effect in accordance with
the provisions thereof and the Loan and Security Agreement is in all respects
hereby ratified, confirmed and preserved. This Amendment and all its provisions
shall be deemed a part of the Loan and Security Agreement in the manner and to
the extent herein provided.

     SECTION 4.  Successors and Assigns. This Amendment shall be binding upon
and inure to the benefit of the parties hereto and their respective successors
and permitted assigns.

     SECTION 5.  Governing Law. This Amendment shall be governed by New York law
without reference to its choice of law doctrine.





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     SECTION 6.  Counterparts. This Amendment may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument, and any of the parties hereto may execute this Amendment by signing
any such counterpart.

                                      * * *





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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 4 to
be duly executed as of this ___ day of August, 2002.

                                             NC CAPITAL CORPORATION


                                             By: /s/ Kevin Cloyd
                                                 -------------------------------
                                             Name:
                                             Title: President


                                             MORGAN STANLEY DEAN WITTER
                                             MORTGAGE CAPITAL INC.


                                             By: /s/ Andrew B. Neuberger
                                                 -------------------------------
                                             Name:
                                             Title  Vice President