User Preference Issue

Using Intralink 9.1 M040, one master site and 3 replica sites.

All of a sudden, all users at one replica site can no longer change any of their user preferences. No security or access control modifications have been made. They see the preference settings, can hit the edit icon and change the settings value, but when they poke the OK button the window hangs.

Has anyone seen this before? Does anyone know where a users individual preferences settings are stored? Is it inside Oracle or are they in a physical file somewhere. If I knew where, I could check the permissions.

Thanks