Here is another way to unlock 05.12.01 / 05.13.04 baseband on iphone, video shows how to activate iphone 3GS, iphone 4 and iphone 3G without the original SIM card. Now use any SIM card with your any of your iPhone, but if you’re an iPhone 4 user then you’ll have to cut SIM to micro-SIM card size before using it. A word of advice is save all of your sim data including contacts before doing this.

(source:surfpk)