blocking using own SMTP server

Hi,

How can I block for ALL users the SMTP server?
I don`t accept sending E-mails from our servers to other mail servers.
If someone wish to send a mail he can use his SMTP of his ISP.

Where can I set this point?

Block port 25 with a firewall.

Chris

Or alternatively, learn how to write ACLs.

I'm currently studying exim ACLs and have ordered the new exim book (the UIT Cambridge one, not the O'Reily one, which is for version 3.x).

I'm going to publish a good spamblocking ACL, and perhaps an entire alternative exim.conf file, shortly.

Jeff