Months of waiting still no solution for the Unlock for the iPhone 4 basebands. When a single solution came up which was the Sim card it’s called GEVE Sim. Which unlock your iPhone 4 on iOS4.1 and iOS 4.2.1 baseband 2.10.04 and 3.10.04. When people heard about it, many of people rushed to purchased it. Many of them will be using it.

Now is it is confirmed by @MuscleNerd that the GEVEY Sim is illegal in USA and Probably in other countries:

That “dial 112 then hang up” in gevey is illegal in USA, and probably other countries. Buyer beware.

The above picture is of the instructions from their video.

If you are wondering what is GEVEY Sim and how it works, so you can see the whole detail here. The reason it is illegal because you have to dial 112 which an emergency number and in U.S.A it is 911. Every time you reboot or get signal lost you have to the same procedure again to gain the unlock. So calling to 911 an hangup is something illegal in U.S.A. In U.S.A if you call to 112 it will convert it in 911 which is not good.

The problem you will face if you get caught while using this Sim or your carrier some how gets to know, so your Sim will get a permanent ban, then a user ban from that carrier.

To stop this kind of activities in U.S.A the carrier will block this kind of activities and Sims.The Dev-Team is working on the proper one Unlock and you should wait for that. Although it’s been  a long time and still no Unlock.