I got my iphone4, it's jailbroken and unlocked. Cut down my O2 sim and it works fine except it won't connect to the internet via 3g. My o2 contract is a palm pre one with unlimited data. I have spoken to o2 and they said that it 's fine to use my iphone on the existing contract (as it's my choice which of my handsets to use) but having changed the network APN and MMS APN to those that they have given me still no joy. One other thing that I noticed when changing the settings was that under SETTTINGS-->GENERAL--->NETWORK---> the titles are MOBILE DATA and MOBILE DATA NETWORK and the O2 guy reffered to these as CELLULAR DATA and CELLULAR DATA NETWORK. Am I doing something wrong? (Wifi works fine by the way)