Is there a way to "erase" tapes via TSM? (Or AIX?)

We have changed servers and tape format (from TSM4.1, AIX 4.something and
a 3575 library) and I am on a quest to "scrub" the old tapes so we can try
to sell them instead of having to destroy them.

Nancy Reeves
Technical Support, Wichita State University
Nancy.Reeves AT wichita DOT edu          316-978-3860