As opposed to preprocessing before using SA to reduce the load. (ie. using blacklist and whitelist before SA)
SMTP -> Sendmail, which uses these to reject: GreetPause RBL: zen.spamhaus.org RBL: dynablock.njabl.org RBL: dsn.rfc-ignorant.org RBL: bogusmx.rfc-ignorant.org RBL: bl.spamcop.net SPF Sendmail -> Procmail feed "spamtrap" addresses or bad domains to sa-learn, then throw away don't filter postmaster Procmail -> SpamAssassin send to /dev/null anything autolearned
