Re: [EAI] draft-leiba-5322upd-from-group discussion

[[e-mail]]

> I think the subject document will do; please review it:
> http://datatracker.ietf.org/doc/draft-leiba-5322upd-from-group

> The "replacement for 3.6.2" section should be solid except for one
> issue, noted: one sentence needs to change, for our purposes, and we
> need to decide how to make the change.

>    If the from field contains more than one address in the address-list,
>    then the sender field, containing the field name "Sender" and a
>    single mailbox specification, MUST appear in the message.

> I don't believe that we plan to use the "Sender" field in the cases
> where we'll use group syntax in "From", so that MUST can't stay.

Then I guess I'm confused. The cases I'm familiar with in EAI at least involve
constructing empty groups. The text says "more than one", not "anything 
other than one", so the MUST would not be violated.

If there's a use-case for creating a From: field using a group that
ends up containing multiple addreseses, I'd like to know what it is so I can
evaluate whether it warrants overrding the MUST.

> The
> simple change would be to make it SHOULD and have done with it, but
> I'm not entirely happy with that.  The alternative is to leave the
> MUST, but add "unless...", and then we have to craft the "unless"
> text.

> Please also review the Security Considerations, and make sure I got that
> right.

The one I don't see is possible exploits involving different clients handling
of something that used to not be allowed.

					Ned