Is it possible to unlock iphone 4g on 5.1 base band 04.12.01?

[doc2142]

My friend bought this phone and is asking me if I can unlock it for him. It is not jailbroken and I looked around the net a bit and I am confused. I read I can use a method called SAM, however, it has been reported that this method is blocked. Can someone please point me to the right direction of how to unlock this phone.

I have been away from unlocking and jailbreaking for a while so I have no idea what is possible and what is not.

Thanks again for helping out!

 

[Applejuiced]

No, nothing you can do to unlock it currently.
Besides calling the carrier its locked to and asking for an official unlock.

 

[dhlizard]

Same exact question here