We are currently auditioning various smartphones running Windows Mobile 5. I understand that not all of these devices have been patched with MSFP, although they should all be able to connect to an Exchange 2003 server. My understading is that without MSFP, you can't take advantage of DirectPush. My question is about the configuration of the Exchange server. Currently, we have only one Exchange server. I tried getting RPC over HTTP to work unsuccessfully with this server in the past. For my mobile devices to connect, what is the best configuration? Do I need to set up another Exchange server in a front end role? Should I set up an ISA server to handle connections? Another ideas or thoughts on this would be appreciated.