RPC Over HTTP – Exchange 2K7/Outlook 2003

I’m looking to configure a new Exchange server for one of my offices. We have someone hosting our e-mail and everyone pulls it down via POP3. My superiors have decided they don’t me to configure the server to host our own e-mail, so we’re going to keep the POP3 configuration. I have a POP connector installed on the Exchange server and it works great. What I want to do now is configure Outlook anywhere. All the how-to’s show how to configure it using FQDN that will be accessible from the Internet. Does anyone know if this can be configured using just an IP address? My server has a static IP so we won’t have the issues associated with dynamic addressing.