There is a SuSE build service for Postfix. I can't check it at the moment but it sould be in the list of community repositories. It is usually a little closer to the current stable release than the other repositories.
The only one I know of is: http://download.opensuse.org/repositories/server:/mail/SLE_10/x86_64/This one has a postfix24-2.4.5-1.1.x86_64.rpm from 2007 which seems to be quite old and unsecure.
Alexander
