How to repair Kerberos?

I used to have a working kerberos on OS X server 10.4. somewhere along the way it stopped working but only in the sense that it won't authenticate anyone. In SA it shows up as running and sudo changeip -checkhostname is good. all the users have Open directory passwords with Kerberos v5 entries in the the inspector. so is there a way to resync kerberos without doing a clean install or other drastic stuff?