RE: Automatic email relay agent?

[Anduin Withers]

> Is there any program that can function as "automatic email relay" agent?
> Basically, I stop all email relay in my fc3 and fc4 systems and allow only
> some ip address range to relay emails.  This way, my users in our subnet
> and
> some users at home (who's ip addresses are known) can use outlook etc. to
> send
> emails.  The problem is that sometimes, some users travel to other cities
> and
> they still want to use outlook to send emails.  Since I don't know thoses
> ip
> addresses, they will get "email relay error".

Why not just have them authenticate?