When closing out of applications on the multitasking bar, my phone never fails to freeze up at some point in the process. This has been a problem since I've had the phone (launch day). This time, the phone froze and instead of coming back after a couple of minutes like it normally does, it rebooted itself. Is this an iOS 4 problem that has yet to be fixed or is there something up with my phone? It's not jailbroken and it doesn't even have more than 10 non-default apps on it. And the few I have are nothing weird - they're all pretty popular apps (ie: Facebook, iMovie, AT&T Mobile, Pandora, etc.).