It happens often that while I'm writing a sms or mms the phone locks,
the screen becomes white and then reboots.
It happens to you too? For curiosity, can you write the firmware version
of your phone? It is under Settings -> Videophone info -> Other Infos ->
SW Version and Flex Version.
Mine:
Versione Flex SE6025AXXH3005
Versione SW R24_U_80.2E.29I
It's the Vodafone Italy brand version.
P.S. If you know a site with no brand firmware, it's greatly accepted
here or into my email

Thanks