I would recommend that you research the use of the 'dd' command. It is a bit complicated and would take too long to explain here, but you could try:
dd if=/dev/rmt0 of=[file name on disk]
If there is anything on the tape, that should grab it. You can then try using 'tar' on the file that is written to disk and see if the contents are still intact.
Darryn
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