iClarified.com brings thorough instructions about unlocking an 1.1.2, 1.1.3 OTB iPhone. The instructions assume you have already jailbroken the particular firmware you would like to be on. This works from 1.1.2 or 1.1.3 firmware, but only if you are on a 4.6 BL iPhone. This means that your iPhone came with 1.1.2 or 1.1.3 Out of the Box. PLEASE MAKE SURE YOU DON’T DO THIS ON A 3.9 BL IPHONE!

Read the entire install/unlock process over at the iClarified website. Please tell us how it went.. :D