I have a 3G that was purchased in Australia and locked to the carrier there. My friend jailbroke it and unlocked it using ultrasnow. I just updated the carrier settings in itunes (that went fine) and updated the OS to 4.2 in itunes -- now after rebooting my Canadian SIM card (Rogers) isn't recognized. The phone says I need to install a valid SIM card and activate it. In itunes, I can't do anything, it says the same thing, that I need to insert a valid SIM and activate the phone. My questions is, can I jailbreak the phone? Or do I need to get a valid SIM card from Australia (and then jailbreak, unlock, etc)? thanks!