Hi. I have an iPhone 3GS 16Gb, bought it from someone. It has a 4.2.1 firmware and wasn't jailbroken when i got it so i did it myself. before jailbroking it did work with any sim card, so i did not need to unlock it. i would like to upgrade to version 4.3.3, and preserve my baseband, 05.15.04. As far as I know this baseband cannot be unlocked yet, so my question is, if i make a custom firmware, keep my current baseband, i am thinking of sn0wbreeze, will i be able to use it like now? with any sim card? or will i need to upgrade the baseband to 6.15.00 just to use it as a phone. i dont really know that much of iphones, so any help is appreciated, or a link or two. Thanks.