UDP and TCP over GPRS

So I've just spent most of today rewriting my networking stack to use TCP, rather than UDP in my final year project at uni (It's a Locative game, called RealCTF, and oh so geeky).

Why do I need to rewrite the networking stack? It's because the GPRS mobile data network (on t-mobile uk at least) seems about as well thought out as a chocolate radiation shield. It would appear that you only get a private IP address on the phone side of things, rendering UDP next to useless (for two-way communication anyway - sending from the client is fine).

So I've had to rewrite it all to use TCP/IP instead. Joy of joys. It wasn't as bad as it could have been though, as for once, I actually planned and componentised the core game engine to to reasonable (read: so many classes my mind bleeds) degree.

If for any bizarre reason, anyone is interested in this game I'm writing, I'll post something on it. I might even include some screen prints.