Wiping tape label - how?

[John Bossert]

Having decided that I want my tapes labeled with "DailySet1-NN" rather 
than "DailySet1NN", when I try to relabel "DailySet100" I get the following:

poseidon(amanda): amlabel default DailySet1-01
rewinding, reading label DailySet100, tape is in another amanda 
configuration
rewinding
tape not labeled

This, even after running "amrmtape default DailySet100"
So, how do I
1) tell Amanda to forget about DailySet100; and
2) wipe the label from/relabel the tape?
Thanks,
-john