From: owner-ietf-smtp(_at_)mail(_dot_)imc(_dot_)org [mailto:owner-ietf-
smtp(_at_)mail(_dot_)imc(_dot_)org] On Behalf Of Todd Herr
Sent: Friday, March 26, 2010 10:02 AM
Subject: Re: New Version Notification for draft-macdonald-antispam-
Has anyone heard of any problems dealing with Yahoo!'s 421 4.16.55?
If not, then we can probably expect the same with x.8.y, yes?
I haven't heard of any MTA that actually looks at ESCs, but that's just me.
I'm interested in the SMTP conversation being the only conversation
that needs to take place about a given message. To the extent that
something like this proposal can get me to that goal, without driving
follow up questions from senders (e.g., "I got 554 5.8.5 unacceptable
content; what do I have to do to make my content acceptable?") then
I'm interested in seeing this move forward.
But can that really be eliminated? It seems to me any generic-sounding reply
text is likely to draw response from some end users at some point, even if the
RFC defining the code used is very precise. And the RFCs don't mandate the
text you use, only the semantics of the specific codes that precede the text.
Some implementors have read the RFCS as requiring specific reply text and have
implemented accordinfly. Which is another reason why I continue to push back
against the idea that we have to coter to every possible form of brokenness
Off hand, I think probably the most popular extended reply code among
systems that support GreyListing use the recommendation in the
author's NON-RFC specification:
451 4.7.1 Please try again later
Jeff's I-D has only has x.8.z classification, so as an "anti-spam"
document, the GreyListing reply code would not gracefully fit. I don't
think people are going to change it it to 4.8.1. Maybe Jeff can add
specific well known extended reply codes to the I-D to codify those
that are not official BCP.