v1.2.28: Added RFC 3848 support
Adds "with ESMTPA", "with ESMTPS", or "with ESMTPSA" if relevant.
This header is used by some spam checkers (such as SpamAssassin) to
v1.2.22 Updated format of Received: header to be more like sendmail
Reworked the "from" portion of the Received: header so that it's in a
format like Sendmail's. This should allow SpamAssassin to do a better
job at detecting the boundary between internal mail servers and the
2003-07-08 Kevin Layer <email@example.com>