I just used the Gevy Ultra S in my US AT&T iphone 4S with IOS 5.1 using a UK Orange pre-paid phone with 3G, while in the UK. All I did the first time was follow the instructions and install the gevey with the new sim, and after about 5 moniutes of seraching it worked, with no pop up messages at all. I also receivec some welcome messages from Orange, but then reset my phone, still with the Gevey and new sim in it. Now, when I turn it back on, it requires me to activate my phone, which is the same method that pops up when I try booting it with the orange sim alone! When I install the original AT&T sim, everything works fine, adn when I switch it to the gevey it goes right back to the iphone activation screen. Is this it, did it only work the once?! And right when you reboot it turns off? Anyone else encountered this problem, or know how to get around it? Help is much apreciated, thanks!