Assumed Characteristics of the Mortgage Loans Underlying the Group 3, 4, 5 and 7 Trust Assets¹: Principal Balance² Weighted Average Remaining Term to Maturity (in months) Weighted Average Loan Age (in months) Weighted Average Mortgage Rate³ Group 3 Trust Assets $  65,000,000 284 69 7.50% Group 4 Trust Assets $300,000,000 348 10 6.75% Group 5 Trust Assets $  50,460,000 328 23 6.75% Group 7 Trust Assets $340,000,000 351 4 5.00% ¹As of November 1, 2003. ²Does not include Group 7 Trust Assets that will be added to pay the Trustee Fee. ³The Mortgage Loans underlying the Group 4 and 5 Trust Assets may bear interest at rates ranging from 0.25% to 1.50% per annum above the related Certificate Rate. The actual remaining terms to maturity, loan ages and, in the case of the Group 4 and 5 Trust Assets, Mortgage Rates of many of the Mortgage Loans underlying the Group 3, 4, 5 and 7 Trust Assets will differ from the weighted averages shown above, perhaps significantly. See "The Trust Assets – The Mortgage Loans" in this Supplement. See Exhibit A to this Supplement for certain information regarding the characteristics of the Mortgage Loans included in the Underlying Trusts. Issuance of Securities: The Securities, other than the Residual Securities, will initially be issued in book-entry form through the book-entry system of the U.S. Federal Reserve Banks (the "Fedwire  Book-Entry  System").  The  Residual  Securities  will  be  issued  in  fully  registered, certificated form. See "Description of the Securities – Form of Securities" in this Supplement. Modification and Exchange: If you own exchangeable Securities you will be able, upon notice and payment of an exchange fee, to exchange them for a proportionate interest in the related Securities shown on Schedule I to this Supplement. See "Description of the Securi- ties – Modification and Exchange" in this Supplement. Increased Minimum Denomination Classes: Each Class that constitutes an Interest Only, Non-Sticky Jump or Inverse Floating Rate Class. See "Description of the Securities – Form of Securities" in this Supplement. Interest Rates: The Interest Rates for the Fixed Rate Classes are shown on the inside cover page of this Supplement or on Schedule I to this Supplement. B-32