[otrs] Own ticket not showing up

Dear all, we just upgraded from 2.0.5 to 2.2.4, -> install 2.2.4 -> dump database from old 2.0.5 -> run sql upgrade scripts -> migrate settings from old to new otrs The users are authenticated against an Acitve Directory. After the upgrade all tickets in the frontend are missing, meaning no user can see his/her own tickets anymore. In the backend everything is fine, and we can see all tickets, Any ideas ? Regards Soeren