I have an iPhone 3GS that was previously running 4.1 jailbroken and unlocked with the iPad Baseband 06.15.00. Last night, I upgraded to iOS 5.0.1 through iTunes by mistake and now, after the phone has completed the upgrade and booted up, it isn't able to activate. When activating (I connected wifi) it times out while attempting to connect to the Apple server, and suggests I either try again or activate through iTunes. When I connect it back to iTunes, iTunes reports that there is no SIM installed. There definitely is and it was working fine prior to the upgrade. Any suggestions on what has gone wrong or how I could fix it? thanks in advance!