Never Jailbroken a iphone before and I'm struggling. I have an old iPhone 3G 16GB. It's software version is 4.2.1 and it's baseband is 05.15.04 Now I have PwnageTool downloaded and it keeps asking me to find the ISPW for the iPhone. I've downloaded a bunch but it seems it's not the correct baseband. I also want to unlock the phone from o2 and use it on t-mobile. Could someone assist me. It's becoming a pain and I've tried for a few hours. But the internet keeps telling me different things, don't update, do this, do that, etc. I just need it simplified. Thanks.