RBL Checks

[spader]

I was wondering if anyone had got the RBL open relay black list checks working on their Postfix/Spamassassin setup. I used their bliki entry to setup Postfix with amavis and mysql http://bliki.rimuhosting.com/comments/knowledgebase/linux/mail/postfix+with+amavis+and+mysql but the RBL checks arent working for some reason. If I can get these on then I think I could cut out prob another 60% of spam.

Any ideas?

[Howie]

I have this for rbl checks in my /etc/postfix/main.cf

smtpd_recipient_restrictions =
reject_rbl_client relays.ordb.org,
reject_rbl_client list.dsbl.org
reject_rbl_client sbl-xbl.spamhaus.org,
reject_rbl_client combined.njabl.org

I've removed the other content, but these 4 seem to help with the spam problem and haven't blocked one valid message yet. I was using spamcop but now only use it as a weighted part of spamassassin.