The Message is ANS1943E (Not ANS1934E):
ANS1943E The operation is not supported: Downlevel server version.
Explanation: The operation cannot be performed because server version is
downlevel.
System Action: Processing stopped.
User Response: Use correct server version.

The backup probably failed on the system objects which require a TSM 3.7.3
or higher server.
The system ojbects are included with DOMAIN ALL-LOCAL with the 4.12 client.
You could specify a DOMAIN statement with only the drives to exclude the
system objects to see if the backup will run successfully.

Tim Rushforth
City of Winnipeg