i got an iphone 4 (bought from celcom) upgrade version from IOS5.X.X to IOS6.1.3, and since the upgrade, no service and signal. Stuck in itune plug-in page. Unable to activate the phone with wifi and itunes too.

Anyone encounter this before?

I'd googled around, some say is hardware issue. or jailbreak device issue. need to unlock but its a unlock phone :|