Re: [Exim] Reject spam after DATA, Multiple user Preferences

On Fri, 10 Oct 2003, Tom Kistner wrote:

> Andrew Lewis wrote:
>
> > What I want to know is if it is possible, in theory or in practice (And
> > indeed, if anyone is doing this I would like to know how): To run
> > antispam checks for all users receiving the mail according to their
> > personal profile, reject the mail if it's marked as spam for some users,
> > possibly listing those users in the rejection message, and then go ahead
> > to quarantine/forward/send the copies of that mail as appropriate? What
> > issues face an implementation like this?
>
> If your "reject" means "reject after data" then this is not possible.
> You can either reject for everyone or noone.

Or you can do what we do, based on an idea we got from this list.

At RCPT time, if the first recipient is a spam-hater (or "normal" as
we call them), then any subsequent recipients who are spam-lovers (or
"sucker" as we call them) get deferred. Conversely if the first
recipient is a spam-lover then any subsequent recipients who are
spam-haters get deferred.

Processing at DATA time then depends on whether we decided it's a
spam-haters or a spam-lovers type of transaction.

The sender will later retry the deferred recipients in a separate
transaction, which of course gets the opposite treatment.

Seems to work OK. And a certain kind of spammer doesn't even bother
to retry, which is nice ;-)