You might want to upgrade to the newer version of SpamAssassin, which supports Bayesian filtering. It will greatly descrease the amount of consumed CPU power and it will also increase the quality of filtering for your mail.

Here's the CPAN module for you.

Also, consider this recent discussion on the subject.

Leonid Mamtchenkov aka TVSET

In reply to Re: OT: Spammers Vs Mail::SpamAssassin and the Winner Is... by TVSET
in thread OT: Spammers Vs Mail::SpamAssassin and the Winner Is... by ptkdb

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