Yeah, know the problem. This is how I clean up my user object library file - Every so often, I export all the objects in my user object library to another place, then I just delete my user object library file, and then reimport all the previously exported objects. This seems to get rid of the deleted stuff that was still being stored in the library file and ensures that you only have what you see (so to speak) in your library file.

Dreams are just nightmares on prozac...
Digital WasteLanD