Are you sure the program terminates? If a program hangs for some reason, no other program can continue, but removing the lockfile will "solve" the problem (well, not the problem - just the symptom, and it might cause data corruption - you are using locking for a reason).

If all the programs that hold the lock terminate, and the file is still locked, the fault lies in your kernel, not in perl. It should be impossible for a file to be locked, without a locking process.

Abigail