[Spambayes] IMAP Duplication

[Larry]

(apologies if this has been covered already)

I just installed SpamBayes to use with Eudora.  I read all my e-mail through an IMAP server.  Whenever SB checks for spam, then Eudora checks for e-mail, I get duplicate headers.  I've logged in to my webmail, and saw that the original messages have been deleted, but not purged yet.  Is there any way to stop this from happening?  I would love to use SB in this way, as it has stopped 95% of the spam I receive at work, and the built-in Eudora filters don't work with IMAP yet.

Thanks,
Larry