Iphone Unlocked But No Signal Internet Working

[man50]

I have iphone 3g with baseband of 06.15 and have ultrasn0w new and it is on orginaly on Vodafone Uk Contract But dont have original sim so couldn't activate so when i put a pay as you go O2-Uk sim in it says O2-Uk and 3G but no signal i tired reseting the Network setting and 3G is off. So Please Help! Also I Cant Activate It says "Waiting For Activation"

P.S
Somthing Werid i noticed when i put in my firends vodafone uk contract i get no singnal but the internet works on 3g but i cant call no one and it wont activate with it.

[ame]http://www.youtube.com/watch?v=eeGj4Yzev1E[/ame]

[balbains324]

I got exactly the same problem with my iphone 3GS with 4.2.1 Jailbroken with redsn0w and unlocked with ultrasn0w. I got O2 contract and I can use 3G internet but no calls. Does anyone have a solution?
I have tried installing bossprefs and resetting it but nothing works.