[Mailman-Users] Virtual hosts

Stephen J. Turnbull stephen at xemacs.org
Wed Apr 11 03:51:02 CEST 2007

Mark Sapiro writes:

 > It isn't AFAICT. I was going to add it, but I am looking for a specific
 > RFC reference. I have looked at several RFCs and I don't see anything
 > that talks about rewriting domains in headers. All I found was RFC
 > 1123 (STD 3), sec 5.2.2

As Lucy van Pelt ("The Doctor is 'In'") used to say to Charlie Brown,

                           THAT'S IT!!!!!!


If you look at RFC 2821, you will discover that in section 2.3.5, it
specifically allows CNAME aliases in the "domain name" part of a
mailbox.  I conclude that only the EHLO (HELO) command (and possibly
the server's greeting messages) has the restriction.  The rationale is
that it is an error-reporting mechanism, which needs to be more
carefully specified since the system is known to be in a problem
state.  See section 4.1.1, which specifies that the host specified by
a domain in EHLO should have a reverse mapping.  Since a CNAME can't
have a corresponding PTR, the restriction in STD 3 follows.

"MX names" are also allowed, for what it is worth.

More information about the Mailman-Users mailing list