IPhone 3g unlock help

[siri+uk]

Hi guys

Got an iphone 3G, I decided to use an activated unlocked 4.2.1 firmware on it, the baseband has updated to 05.15.04, which I believe is a firmware that cannot be unlocked. I bought the phone second hand from ebay so don't know the original number or any passwords that were on the account. In settings it gives the carrier as T-Mobile UK 9.1. If I was to go to T-Mobile shop near me would it be possible to get an unlock code for it without the details mentioned.

TIA

[autoelectrics]

With O2, you actually need to know the phone number, and it is all done online, but with T-mobile it may be different, just browse their web, HTH.

[Canker_Canison]

If you're willing to lose the GPS from the phone you can still unlock it.

Jailbreak with Redsn0w & change the baseband to Ipad 06.15.00 then install Ultrasn0w through Cydia.