Postfix/Spam_handling
From http://archives.neohapsis.com/archives/postfix/2010-02/0075.html
Stop 70% or more of all spam with
smtpd_recipient_restrictions = permit_mynetworks reject_unauth_destination reject_rbl_client zen.spamhaus.org
- Stop other zombies with greylisting, e.g., with postgrey.
- If the remaing spam bothers you, look into amavisd-new and other deep inspection systems. Use these only for mail that isn't cleaned via other means.