21 Before proceeding with this tutorial, and at the risk of possibly overstating what is obvious to some, I want to make three things clear: How to get DKIM and DomainKeys working with Postfix on ...This entry was posted in Linux Reference Technology and tagged CentOS CentOS 5 CentOS 5.5 CentOS 5.x dk-milter DKIM DomainKeys DomainKeys Identified Mail OpenDKIM opendkim-milter Postfix RHEL RHEL 5 RHEL 5.5 Sender Policy Framework sendmail signed SPF on January 25, 2011 by Steve Jenkins (updated 3832 days ago)