Roles problem between Online NT and Online Unix

Hi people, I've got a problem that I just can't crack. An app creates some tables, such as fred.user fred.department fred.request I've got a role called fredrole, that all the permissions are granted to, and when a user logs in, the command SET ROLE FREDROLE is issued. All permissions are revoked from the public role. The users start to use the system, and on NT this works perfectly as expected, with users finding the above objects. But on the Unix system, it has a fit, claiming it can't find the objects. As far as I can determine, they are configured exactly the same. Anyone have a similar experience, or any suggestions? Ciao Fuzzy :-)