* Andreas Metzler <eximusers@???> [2003-10-12 19:55]:
> On Sun, Oct 12, 2003 at 05:54:36PM +0100, Alan J. Flavell wrote:
> > On Sun, 12 Oct 2003, Andreas Metzler wrote:
> >> (or a CNAME resolving to an A or an MX record.).
[...]
> Has anybody got a list of MTAs who cannot handle this, besides the one
> used by mx00.schlund.de?
Sure, they cannot handle this? AFAIK they're using Exim 3.x who
should be able to handle CNAMES correctly. :-)
But the setup of Mailhandling within Schlund/1&1 is somewhat
"special" and has some caveats.
According to
http://cr.yp.to/im/cname.html QMail and sendmail aren't
handling CNAME RR's correctly, because they're rewriting envelope
addresses (and sendmail also message headers) to the result obturned
by the CNAME Record.
As far as I understand RFC 2821, Section 5 this is not allowed and
djb mentiones this in his document, too (but didn't implement it
correctly).
Dominik
