Recently, I added the below line to my sendmail.mc and rebuilt. Everything was working just fine until sometime today. In looking over the maillog, it seems if almost every piece of mail was rejected because of this configuration - mail that I know is OK, valid, and not a source of spam, like tamu.edu. Not only that, but the mailing list from centos was being rejected as well. Anyone know what might be happening? One link I ran across said that ordb.org went out of business or stopped their service in Dec of '06. If that's the case, why is their info still being listed in some of the sendmail configs, and others still advertising it's use.
dnl # FEATURE(`dnsbl', `relays.ordb.org', `"550 Email rejected due to sending server misconfiguration - see http://www.ordb.org/faq/%5C#why_rejected%22%27)dnl
Sam