Apple's support forums are humming with reports of iPhones gone non-responsive after their owners upgraded to version 3.1 of the firmware, and users are growing increasingly restive at Apple's steadfast denial that any bug exists. When the error occurs, the iPhone isplay appears to be functional, but does not react to any input on the touch screen or external buttons, and needs a hard power cycle and reboot before it will work again. The problem - dubbed "Coma Mode" for the phone's complete lack of interactivity when it gets in this state - has been noted sometimes when the phone has been put to sleep, sometimes when it's locked, and sometimes at completely random moments.

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