I run a script across all my media servers (all unix) that sends me an
email with the following output...

Frozen Media Report for 07/30/04
HH0874, it is unmountable and cannot be used for backups
HH1212, it has had at least 3 errors in the last 12 hour(s)
HH1264, it is unmountable and cannot be used for backups
DH2869, External event caused rewind during write, all data on media is
lost

And so on and so on...

I can send the script if interested...