On Fri, Mar 9, 2012 at 5:16 PM, Craig Whitmore
I just recently started checking DKIM on a mail server and I've noticed it is rejecting a number of emails including one particular persons posts on the NZNOG mailing list because of DKIM.
Mostly because of issues like mailing lists (and forwarding) DKIM will frequently break for otherwise valid email messages. For this reason, it is not recommended to use a failed DKIM test as the sole reason to reject a message. You should instead use the failed test as a score that triggers more paranoia, but not an outright failure. You could argue that mailing lists should 'clean up' DKIM headings which would help in your specific example, but other use cases will result in the same problems. -jim