Fitch Affirms & Removes Class A-3 of WAMU 2004-RS1 Insured by XLCA from Rating Watch Negative

Business Wire, March 13, 2008

NEW YORK -- Fitch Ratings affirms and removes from Rating Watch Negative the following class of residential mortgage-backed securities (RMBS) insured by XLCA.

--Class A-3 affirmed at 'AAA', removed from Rating Watch Negative.

Fitch's policy is to maintain ratings on insured transactions at the higher of the underlying rating of the insured transaction if rated by Fitch or the rating of the insurer.

On Jan. 24, 2008, Fitch downgraded XLCA's Insurer Financial Strength (IFS) rating to 'A'. XLCA's IFS rating remains on Rating Watch Negative. For more information please refer to 'Fitch Downgrades SCA and XLCA/XLFA; Ratings Remain on Watch Negative, dated Jan. 24, 2008, available on the Fitch Ratings web site at www.fitchratings.com.

Fitch's rating definitions and the terms of use of such ratings are available on the agency's public site, www.fitchratings.com. Published ratings, criteria and methodologies are available from this site, at all times. Fitch's code of conduct, confidentiality, conflicts of interest, affiliate firewall, compliance and other relevant policies and procedures are also available from the 'Code of Conduct' section of this site.