I purchased an unlocked phone from the UK. I cracked the screen and got it replaced. It seems as if I was given a refurb. I didn't complain because it was on Ios 4.1 and that allowed me to jailbreak. However I am now traveling in Africa and want to swap SIM cards. I haven't had to swap since when I got the phone from the UK. I instantly put a Norwegian SIM card and it worked. Now when I put in the african sim card it goes to DFU mode with the usb and the disc. If I take the sim card out and put the original sim in it works fine. Since I have done that now when I go to Itunes it says it can't recognize the content on my phone and I can't back it up. Is a restore in order and if I restore will it revert back to it's factory unlocked condition? Has anyone seen anything like this?