Re: I-D Action:draft-newman-email-subaddr-01.txt

Stephane Bortzmeyer <> Mon, 03 December 2007 09:43 UTC

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Date: Mon, 3 Dec 2007 10:43:51 +0100
From: Stephane Bortzmeyer <>
To: Dave Cridland <>
Subject: Re: I-D Action:draft-newman-email-subaddr-01.txt
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[No discussion list indicated in the draft, trying the Application
Area general list.]

On Fri, Nov 16, 2007 at 12:50:01PM -0500, <> wrote 
 a message of 97 lines which said:

> 	Title           : Internet Email Subaddressing
> 	Author(s)       : D. Cridland
> 	Filename        : draft-newman-email-subaddr-01.txt

I'm quite puzzled by this draft and I do not really understand what it
normalizes or what its purpose is.

The entire idea of subaddressing is to be a local decision, only the
final MTA and/or its MDA will have to know it. Besides stuff like RFC
3598, there is little room for IETF work. 

Some sentences in the draft are strange, in that respect. For
instance, section 4.2 says "A subaddress-aware gateway or firewall
SHOULD preserve the detail part when rewriting an address." while I
thought that the SMTP rule was much stronger: "DO NOT MESS with
addresses", and that is a general rule, it is not only for

Apart from that, the draft puts too much emphasis on the most common
"+" (with a MTA like Postfix, it is trivial to change it - the
recipient_delimiter option, and many people do so to avoid the problem
of broken software mentioned later). Again, the IETF should not
mention this separator, since it is a local decision.

Strangely enough, the draft does not talk about *the* big problem with
subaddressing: the fact that many stupid and broken Web forms and/or
mail software do not accept them or do not handle them
properly. Certainly, an informational RFC asking to accept valid email
addresses would be an useful document. See a good start in, specially the conclusion
("There is some danger that common usage and widespread sloppy coding
will establish a de facto standard for e-mail addresses that is more
restrictive than the recorded formal standard.") or in
(the comments are interesting, too).