On ppc64 systems running SuSe Linux version 11.4 NSS calls are failing. This results in commands such as "id" returning nothing for the user and ssh returning errors that the user doesn't exist.
The vastool commands operate correctly because they are using 32 bit binaries which do not see the issue. For example "vastool user checklogin" and "vastool nss" queries will run as expected.
Waiting for fix in a future release of Authentication Services.