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Re: rfe: automagic open relay message refusal?

Alexey Lobanov <aal@cpr.spb.ru>
> 1. Seems, it is not an Unix Way. SMTP server should not generate 
> outbound SMTP connections :-).

That's not the "unix way". That's how it has to be.

Suppose that you run such a thing, and that you implement the SMTP
timeouts exactly.  Suppose further that mumble.com does the same.  What's
going to happen when you receive mail from mumble.com?

When you see the RCPT TO, you'll open an SMTP connection to mumble.com in
order to detect whether mumble.com's an open relay and when you say RCPT
TO, that machine opens an SMTP connection to _you_ to check whether _you_
are an open relay.

At this point, the smart MTA realizes that it's already doing the test,
and doesn't open a fourth connection. But what does it do?  What can it

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