MELBOURNE (Standard&Poor's) Oct. 16, 2006--Standard&Poor's Ratings Services today said it had assigned its preliminary ratings to the A$3 billion global issue of Australian residential mortgage backed securities (RMBS) by National Australia Bank Ltd. (NAB) through its National RMBS Trust 2006-3 (see list). The three classes of floating-rate notes are backed by prime Australian residential mortgage loans. The preliminary ratings are based on information as of October 16, 2006. Subsequent information may result in the assignment of final ratings that differ from the preliminary ratings. A copy of Standard&Poor's complete presale report for this transaction can be found on RatingsDirect, Standard&Poor's Web-based credit analysis system, at www.ratingsdirect.com. The presale can also be found