Help! iPhone 3g, 4.0.2 call failed/call forwarding

[kaos-nw]

Hi everyone, I have just brought a iPhone that is on 4.0.1. I JB it and installed ultrasn0w to unlock it

Now when I put my sim in the phone it shows full signal and displays T-Mobile in the top left corner but I cant make or recieve any calls at all! when I try and dial any number it almost instantly says 'call failed' beeps three times and displays a pop up saying call forwarding active, with a dismiss button

I also cannot send text messages, But I can use 3g without problems

I have read load and have tried changing the time/date settings, show caller ID, disabling flight mode/3g etc and nothing seems to work!

It was a fresh install of 4.0.1, all I have done is jailbreak it and unlock it. Does it need activating or something???

Please can someone help me!

[mjbnock1]

one of two things you will need to activate with an original sim, or as my friends phone it has been blocked.

[kaos-nw]

Thanks mate, since posting I think ive found out its most likely been blocked! so the IMEI wont work in the UK, so im either going to try and find someone outside the UK to buy it, or somehow get it working here