relays.ordb.org is out of business (see
http://www.cyberciti.biz/tips/ordbor...g-offline.html)
Try following RBL:
Code:
reject_rbl_client list.dsbl.org,
reject_rbl_client sbl.spamhaus.org,
reject_rbl_client cbl.abuseat.org,
reject_rbl_client dul.dnsbl.sorbs.net
See complete tutorial
Postfix configure anti spam with blacklist