Re: Intent to revive "expires" header from draft-ietf-mailext-new-fields-15

Paul Smith wrote:

> All I can figure out so far is that the expiry of a
> message implies it's possibly not quite as important,
> urgent or valid to the sender/recipient/some-other-
> person as it would have been before it expired.
 
> I'm not sure that's a tight enough definition :)

From a sender's POV "expired" could mean "if you read
this mail later whatever I wanted is not more relevant".

Examples:
"confirm your subscription to list X in the next 3 days"
"special offer valid until 2008-06-30"
"I'm out of office until 2008-07-18"

Good examples apparently require some kind of mailbot
on the sender's side.  It is less useful for ordinary
(sending) MUAs, e.g., "happy birthday" with Expires: 
makes no sense, or does it ?

 Frank