Ok so I'm having some troubles "unlocking" my iPhone to use with another carrier or even a pre paid sim. It just dosen't seem to work for me. I have a 16GB iPhone 3GS(Model MC132X) with 05.13.04 baseband, jailbroken with Jailbreakme.com I downloaded the lastest Ultrasn0w through Cydia and installed without a hitch yet iPhone still wont seem to let me use any simcard at all to make calls. I seem to be quite stuck and don't know where I went wrong. Any help would be HUGELY appreicated.