I had a very annoying problem occur the other day when my phone had been in Offline mode while on a plane. When I tried to turn the radio back on, the phone refused to exit Offline mode. Tried many times to force General mode but to no avail. Finally had to do a complete phone reset, which of course nuked everything I had on the phone -- themes, settings, contacts, everything.
Very annoying. A couple more incidents like that and you'll find it on eBay.