what are ipad .panic.plist

My iPad2 keeps crashing, I see many .panic.plist events in diagnostics and usage which shows panic(cpu 0 caller 0x807db6df): "i2c2::_interruptFilter interrupt when no transaction in flight;last read status.

Does anyone know what this means? I have preaviously done a factory reset and full restore but the crashes keep happening. Some days no crashes then the next day maybe 5 in an hour. Before upgrading to iOS5 I loved my iPad no problems and no resets but since upgrade things have been getting worse.

Please help if you can. Regards.