This is one of the d@mndest problems I have run across in a while :

I have an iPhone. My boss has an iPhone. Our company has e-mail. I configured my iPhone to access IMAP (both the company and gmail) and it works fine. I also tested POP which works fine. We configured his and it wouldn't work. I held them side by side and duplicated the config, even configured his phone with my account info to test and it wouldn't work. The mail preference screen accepts the information, seems to verify it and takes you back to the settings page. When you go to the mail application and click to load the e-mails it will time-out before ever pulling any of them. Mine works fine. They were both running over EDGE, WiFi was off (company firewall blocks IMAP connection).

Sadly he had to go to a meeting before I was able to figure out the answer... Any thoughts? He said that he initially had it working through POP but then it stopped working without explanation. I am totally at a loss and he's considering going back to his old phone since this has been such a hassle- can't let it happen!!! Thanks.