[Spambayes] Database cleaning?

[Leonid Broukhis]

Dear Developers,

many thanks for the cool program, it helps already, just a few hours after
installation. I have a question, though: the spammers actively employ
subject line chaffing (inserting nonsensical words or random letter
sequences): does this cause database pollution and is there a way to weed
those (usually unique) entries out?

I only have 200 Mb in my "virtual server" ISP account, and the database is 
closing up to 3 Mb after one day.

Thanks,
	Leo