-----Original Message-----
From: owner-ietf-smtp(_at_)mail(_dot_)imc(_dot_)org
[mailto:owner-ietf-smtp(_at_)mail(_dot_)imc(_dot_)org] On Behalf Of
ned+ietf-smtp(_at_)mrochek(_dot_)com
Sent: Tuesday, February 28, 2012 7:54 AM
To: Arnt Gulbrandsen
Cc: SMTP Interest Group
Subject: Re: MUA support for multiple from addresses
If you goal is to sign absolutely everything you send, I would dispute
the notion that DKIM is actually competent for that. In particular,
DKIM fails to handle the "send on behalf of" case. The proper way to
handle that - and it's widely supported and commonly used - is to put
the "on behalf of" address in the From: and the actual sender's address
in the Sender:.
I think the DKIM protocol is orthogonal to this logic. It's the software
deciding what to sign and with which key that needs to have this logic, not
DKIM itself.
-MSK