[imp] IMP as an open relay

[Chuck Hagenbuch]

Quoting Jan Schneider <jan@horde.org>:

> No, I think he is right because he didn't say that someone can relay with
> another mail server but (to keep this example) our demo server once he's
> authenticated using any external imap/pop server.

No.

If we tried to follow his suggestion and made the user supply an SMTP 
server, chances are about zero that we could actually _use_ that SMTP 
server to send mail on the user's behalf.

IMP demo site -> connects to user's local SMTP server -> tries to send mail 
to someone not at that ISP -> Whoops! Relaying denied.

It's just not feasible for the vast majority of cases.

-chuck

--
Charles Hagenbuch, <chuck@horde.org>
My intuitive grasp of mathmatics often leads me astray.