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Re: Using RSET with the EHLO/HELO fallback logic

2008-02-25 22:39:46

--On Monday, 25 February, 2008 18:08 -0500
Valdis(_dot_)Kletnieks(_at_)vt(_dot_)edu wrote:

On Sun, 24 Feb 2008 16:16:02 EST, Hector Santos said:

   S: 220 **************************************************
   C: EHLO
   S: 500 Syntax error, command unrecognized

Am I the only one who thinks that if the remote end doesn't
understand EHLO, it's highly unlikely that any revision of
2821 is going to improve matters?  RFC1425 was a *long* time

Yep.  And, of course, that is also why the second paragraph of
2.2.1 ("Contemporary SMTP implementations MUST support...") says
what it does.  The theory, going back to early discussions in
DRUMS, is that support for EHLO is now mandatory and so the
fallback cases should not arise.  One's alternative is to
conform to 821 only, in which cas, as you suggest, anything
2821bis says is likely to be irrelevant.

It continues to be reasonable to have some instructions in
2821bis about interoperation between 2821/2821bis
implementations and 821 ones, but we shouldn't expect the latter
to change their behavior without also becoming 2821-conforming.