Spamassassin stopped working

[Victor DiMichina]

I fed a few messages to spamassassin yesterday,  and rebuilt the
database.  BAM,  it stopped working,  or works at about 20% of its
former success rate.  It gave me some feedback about "expired old bayes
database entries"   and gave a number of tokens it kept,  and the number
deleted.   This is the first time I'd ever seen this message,  and now
it doesn't work.   Any suggestions?

I've already done a --forget on the files I learned yesterday,  but it
hasn't helped.

Thanks
Vic