on your security may occur much earlier than the final distribution date. Support securities will be more sensitive to rates of principal payments than other securities. If principal prepayments result in principal distributions on any distribution date equal to or less than the amount needed to produce scheduled payments on the PAC and  TAC classes, the related support classes will not receive any principal distribution on that date (other than from any applicable accrual amounts). If prepayments result in principal distributions on any distribution date greater than the amount needed to pro- duce scheduled payments on the related PAC and  TAC  classes for that distribution date, this excess will be distributed to the related support classes. The rate of principal payments on the un- derlying certificates will directly affect the rate of principal payments on the group 2, 6 and 7 securities. The underlying certifi- cates will be sensitive in varying degrees to •   the rate of payments of principal (includ- ing prepayments) of the related mortgage loans, and •   the priorities for the distribution of princi- pal among the classes of the related under- lying series. The principal entitlement of the underlying certificates included in trust asset group 7 on any payment date is calculated on the basis of schedules; no assurance can be given that the underlying certificates will adhere to their schedules. Further, prepayments on the related mortgage loans may have occurred at rates faster or slower than those initially assumed. This supplement contains no information as to whether the  underlying certificates  have adhered to any applicable principal balance schedules, whether any related supporting classes remain outstanding or whether the underlying certificates otherwise  have per- formed as originally anticipated. Additional information as to the underlying certificates may be obtained by performing an analysis of current principal factors of the underlying certificates in light of applicable information contained in the related underlying certifi- cate disclosure documents. The securities may not be a suitable invest- ment for you. The securities, especially the group 2, 6 and 7 securities and, in particular, the special, support,  interest only,  principal only,  inverse floating rate,  interest only in- verse floating rate, accrual and residual clas- ses,  are  not  suitable  investments  for  all investors. In addition, although the sponsor intends to make a market for the purchase and sale of the securities after their initial issuance, it has no obligation to do so. There is no assur- ance that a secondary market will develop, that any secondary market will continue, or that the price at which you can sell an invest- ment in any class will enable you to realize a desired yield on that investment. You will bear the market risks of your invest- ment. The market values of the classes are likely to fluctuate. These fluctuations may be significant and could result in significant losses to you. The secondary markets for mortgage-related securities have experienced periods of illi- quidity and can be expected to do so in the future. Illiquidity can have a severely adverse effect on the prices of classes that are espe- cially sensitive to prepayment or interest rate risk or that have been structured to meet the investment requirements of limited catego- ries of investors. The residual securities may experience sig- nificant adverse tax timing consequences. Ac- cordingly,  you  are  urged  to  consult  tax advisors and to consider the after-tax effect of ownership of a residual security and the suit- ability of the residual securities to your in- vestment objectives. See "Certain Federal Income Tax Consequences" in this supple- ment and in the base offering circular. You are encouraged to consult advisors re- garding the financial, legal, tax and other aspects of an investment in the securities. S-11