On Tue, Jul 17, 2007 at 05:01:27AM -0400, John C Klensin wrote:
Excuse me, but why is this complicated?
While PRDR may be very useful, it isn't needed here. More
important, if the message really is spam, the odds that the
spammer will request PRDR seems to me to be slight to none...
and it might not be desirable to give the spammers that much
information if they did ask for it.
So you have
C: MAIL FROM:<spammer(_at_)example(_dot_)com>
S: 250 OK, I suppose
C: RCPT TO:<spamtrap(_at_)example(_dot_)org>
S: 250 Ok, amuse yourself
C: RCPT TO:<mailing-list(_at_)example(_dot_)org>
S: 550 As far as you are concerned, no such address
C: DATA
S: 354 Go
[...]
Is there something I'm missing?
It is about content, not about sender address.
If the content is spam, <spamtrap(_at_)example(_dot_)org> does want it,
<mailing-list(_at_)example(_dot_)org> does not.
You can only tell after DATA is finished.