i Phone 4g with Baseband 3.10.1 and 4.10.01

 Gevey SIM interposer, a TurboSIM-like piggy back sim card that allows you to unlock any iPhone 4. When we first wrote about it, we raised concerns about the legality of this method, and warned you that your carrier might not like you using this.

 the Gevey SIM is indeed illegal in the US and most likely in other countries because it dials the 112 emergency number and hangs up right away…

Dialing this 112 phone number is basically like dialing 911 here in the US, which is illegal, unless you’re calling for a good reason of course.

Because the 112 call has to be made every time you reboot your unlocked iPhone, it will most likely get you in trouble in the long run. First, your SIM might be banned by the carrier, and you might even be banned as a customer.

Note : Dial 112 and hang up after the call is connected (Means One Signal Bar In Devise). The network issues a TMSI for your connection

The Next Step Toggle flight mode On/Off. What exactly happens is not too clear but apparently the interposer ROM block electrical connection to prevent the BB from detecting the fake IMSI 

The signal bars appear, we are safe:-) That is after the network ignored the fake IMSI (which the phone has no knowledge of) but allowed the SIM onboard because it is able to validate that.