I'm sure that many of you know about this: http://www.ietf.org/mail-archive/web/ietf/current/msg87153.html
and are dealing with the fallout. I'm interested to know what people are doing about it. Does anyone have working plugins? I've seen suggestions about rewriting From addresses, and there's another one here - selectively rejecting messages with troublesome From: addresses with: 5.x.x DMARC p=reject not compatible with email sent to a mailing list http://www.ietf.org/mail-archive/web/ietf/current/msg87253.html