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Re: [ietf-smtp] New Version Notification for draft-crocker-email-deliveredto-00.txt

John R Levine <johnl@taugh.com> Fri, 12 February 2021 17:25 UTC

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Date: Fri, 12 Feb 2021 12:25:12 -0500
Message-ID: <def1807a-9a37-c15e-a86b-b1b2f88ed4@taugh.com>
From: John R Levine <johnl@taugh.com>
To: Pete Resnick <resnick@episteme.net>, dcrocker@bbiw.net
Cc: ietf-smtp@ietf.org
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Subject: Re: [ietf-smtp] New Version Notification for draft-crocker-email-deliveredto-00.txt
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> The examples show Delivered-To: next to the last Received: field, which 
> implies that Return-Path: is going to get pre-pended after the Delivered-To: 
> field. If in practice they can appear in either order (which seems perfectly 
> plausible), that seems like a reasonable thing to mention. ...

Depends on the implementation.

If you want to add helpful advice, I'd also add Sam V's point that it's 
widely used to break mail loops.  I think that every MDA that adds 
Delivered-To checks to see of the message already has the same D-T and if 
so drops or bounces the message.

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

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