Hi,
I have enabled SpamAssassin on common-lisp.net - This should reduce the amount of spam that passes the system significantly. Spam filtering is performed during SMTP receiption and the threshold is very low. False positives will travel back to the sender with the message that the email was considered spam, so I don't think that the low threshold should be a problem. If there are still reports about spam passing through our mailer, I'd like to learn about it and maybe tune the system more.
Cheers, Hans