Chris Haynes wrote:
[ a bunch of stuff with which I agree, followed by: ]
In my view:
1) To introduce the Expires header with a semantic which permits the mail
system to silently discard messages (wherever the message is at that time)
would be bad requirements engineering,
2) The only possible role for such a header would be as a 'hint' to recipients,
who may opt to give their user agent permission to delete messages (probably
selectively - based on sender, topic, etc). But such a 'hint' (and its
implementation) should not be discussed and defined at the 822 architectural
layer - it does not belong here.
So, FWIW, I think it is a bad idea to consider it in an 822 forum - whatever
semantic is attached to it.
I think it's rather odd that people are arguing that a proposed
extension to the 822 (i.e. user-to-user) protocol can only be used by
what is arguably mail transport (or on the boundary between transport
and the recipient's user agent). It certainly doesn't belong in SMTP.
Nor does it belong in a body part, since it's clearly a message-level
Where else can we put it?