On Tue, 4 Aug 2015, Brian Kantor wrote:
  Thanks. We're currently running 2.1.14 which
doesn't; I'll look into
 updating it.  Unfortunately, the fix involves changing the way that
 message addresses are formatted which could cause some problems. 
That's correct.  The munge-from option adjusts the from address to be the
list-address and moves the sender address into the reply-to address only
for the DMARC-specific recipient.  If the recipient's domain doesn't
specify a DMARC policy, the from-address is not touched.
This does add a small amount of DNS lookup overhead for each recipient.
Antonio Querubin
e-mail:  tony(a)lavanauts.org
xmpp:  antonioquerubin(a)gmail.com