I thought this was an issue with my first IP4 before I had it swapped for a new one, but the other day this happened again so I'm not sure it was isolated. I've noticed sometimes when I "hold it wrong" and lose all signal including 3G, I occasionally have to flip Airplane mode on and off to get it to come back. A few times when this has happened, I've switched Airplane mode on and I get a message that says basically 'enabling Airplane mode will end your current call'. However, I am most decidedly NOT in a phone call. What's even weirder is if I do enable/disable, and try to enable Airplane mode again, it will still say that. I have to actually reboot the phone to get it to go away. Has anyone else seen this behavior? My biggest concern is not necessarily that I have to restart it (although it is annoying), but rather than I'm unknowingly in a call despite no signs, and that I might be calling people without my consent.