Exchange Behind Firewall?

Put your Server behind the firewall and open the necessary ports to it.

Remember, exchange2k needs to be in an active directory setting. It needs to be able to talk to other DC's in order to authenticate users.

If you are not in an AD settingand have no plans to migrate, I reccomend going with exchange 5.5.

Again behind the firewall, and the exchnage server is part of your domain for authentications.

Now here is my 2 sense, I personally would not use IMAP if I am taking the time and effort to set up and maintain exchange.

In order to grasp the full funtionality of exchange, use it as intended. With all clients using outlook configured for exchange.

It takes a little more work, but in the long run it is worth it. Also I strongly reccomend setting up secure communications between your end users and the mail server. The last thing you want is domain passwords being broadcast in plain text. (we use a vpn authentication system)

Good luck

Thats how we did it in our school
the server is behind the firwall and the we opened the necessery ports and now everything works great.
this way you are more secure too