[ On Tuesday, March 18, 2003 at 23:20:59 (+0100), Florian Weimer wrote: ]
> Subject: Re: [Exim] Reaction to rude 554 greeting
>
> If it was properly documented, we could argue about the sanity of its
> semantics.
I still fail to see anything at all that could be even remotely
confusing about the defined purpose and behaviour of a 554 response in
return to the initial connection. RFC 2821 Section 3.1 reads _very_
clearly to me, and the definition of response codes in general is also
reqsonably clear.
Of course there doesn't seem to be any reason for its special mention in
section 3.1, which I suppose could be construed to being somewhat
confusing, but I would suggest this aspect could only be confusing to a
person not familiar with reading IETF RFC documents.
> Given the wild disagreement among implementations in this area, I
> think it's impossible to use it in a reliable manner (except for
> annoying people and starting endless discussions).
What implementations are you talking about? While my knowledge of these
things is far from complete I'm not aware of any SMTP server
implementation which will return any 5xx in response to the initial
connection and I'm not aware of any current SMTP client implementation
which won't return a bounce when it receives a 5xx response to its
initial connection. All attempts by folks responding to this thread to
show such an implementation has, as far as I can remember, failed.
The only possible purpose for a 554 response after the initial
connection is, as the RFC effectively says, for some host which must
answer on port#25 for unspecified reasons, but which never speaks SMTP
on port#25. It's a safety measure to prevent users from being confused
if they somehow cause their client-SMTP mailer to route to such a host
by accident.
--
Greg A. Woods
+1 416 218-0098; <g.a.woods@???>; <woods@???>
Planix, Inc. <woods@???>; VE3TCP; Secrets of the Weird <woods@???>
