I recently tried to use the airplane mode in an airplane 
. I was using the audio player, and was going to try to access the onboard WiFi. The phone acted OK for about 3 minutes, then the media player became intermittent, and the phone totally unresponsive. I hit the power button a couple of times, nothing apparently happening, but finally the phone rebooted. I repeated, and the phone did the same thing after a few minutes. I tried it while paging and keeping the screen from timing out, and that didn't help - still froze up. Finally, after rebooting a couple times, I turned it off on purpose with the airplane mode off. Once on the ground, I had to reboot twice to get the phone to behave correctly. Anybody else? I wonder if this will be corrected in Android 2.2, of if it is time to get a replacement phone.