I have an iPhone 3g on a jailbroken iOS 3.1.3 (7E18). The modem firmware is 06.15.00. I've reinstalled this software update twice because each time Cydia crashes, saying "Loading Data". I just want to jailbreak and unlock the iPhone so I can use it. Is there any way to update it and unlock it safely, while being jailbroken? (I'm a n00b at this stuff).