Upgraded to 4.2.1.7 (AIX) from 4.2.0.1 this morning and it went well. All of the
old problems seemed to go away, but...

I just had a wierd thing happen.

We have 6 drives in our library and 5 drives in use (1 move data and 3 
backuppool
migrations).

Then the move data and one of the migrations gets cancelled by a "higher
priority operation" requesting the tape drives. The thing was, there was no 
process
or session wanting a tape drive, or the tapes.