[otrs] ldap sync

Hi, upgraded a while back from 2.4 to 3.0.9. Now when new users try to login they get a "panic" error message and it doesn't do anything further. i then have to create user manually and then it works. Has anything changed with the LDAP backend structure. the only change i see from the documentation is the old 2.4 way was called "AuthModule" and the new is called "AuthSyncModule". Does it allow both or must i change to the new way? Can't test as it's a live system. thanks for any info. Neil