5 - 6.5 sp5+patch servers in 5 different locations (Not connected with
each other) with either a DAT72 or LTO2.
Backup Exec 9.1 (different point releases)
Full Backups Saturday morning
Differentials the rest of the week.

Have had no errors with the backups since any of these servers went in
(up to 18 months ago - newest is 4 months old).

All 5 performed the full with no errors on Saturday.
All 5 errored on Sunday and Monday with the same error appending to the
tape used on the same tape as the Saturday backup.
The tape retensions and then the backup finishes with the following error:
Job Completed: With ERROR - Appendable media was not found for the
specified media set.

No configuration changes have been made to BE
Absolutely the only thing that has changed is DSTShift.nlm was applied
to all of these servers over the past few weeks.
One of the servers was restarted after DSTShift was applied, but the
other five have not been. They all report the time correctly with the
changed DST days.

No other errors reported other than the backup.
Considering this is not an isolated incident I have to assume it is
something with Netware. Note that all servers act as the primary NTP
server with the same ip address as the source .

This may be the wrong forum for this but I am starting here(nothing
found at Symantec either).

Any thoughts? Thank you!