[Greylist-users] Does Greylisting *always* work?

[Corey Huinker]

> I'd argue that the originating server isn't following the RFCs as intended
> (though possibly as written) because greylisting doesn't temp-fail the

Consider the case of your SMTP server attempting to deliver 200 messages
to yahoo.com, and one of those users has a full mailbox.  The yahoo SMTP
server will tempfail mail to that one mailbox, and accept the rest.  If
your "RFC compliant" server gave up after a single user tempfail, then it
would already be buggered up by a single full mailbox, a situation that
happens in real life all the time.  The sending SMTP server can't tell WHY
it got tempfailed (the recipient server could be lying), just that it did.

Initially, I thought the same thing, so I ran that scenario past Evan a
few weeks ago.  He showed me the way to enlightenment. (bows head, gong
sounds).