I'm still pretty new to TSM so please be gentle with me.

I have inherited control of a previously externally-managed TSM 5.3 system and 
have been chasing a problem where there always seem to be tapes in the vault 
that shouldn't be there. After much chasing, it appears that the extras are DB 
Backup tapes that have been sent to the vault, then subsequently expired. 
Unlike offsite copy tapes that are expired through reclamation, the expired DB 
tapes don't appear to be flagged in any way so, unlike reclaimed offsite copy 
tapes, they are not given a Vaultretrieve status. The DB backups just vanish 
from the system and it's neccessary to trawl through the histories of these 
volumes as they are found.

I'm pretty sure it shouldn't work this way so can anybody recommend some best 
practice for handling expired DB tapes?