I bought a second hand EF81 few days ago, it is T-Mobile Version flashed with chinese firmware, but it is very unstable and many bugs, sometime can't recognise the micro SD card, sometime can't take photo, slow in operation, sometime reboot......so bad. I saw the post from mobile01, there are some problem on the chinese firmware, that's the reason why it haven't release in asia. Anybody know how I can flash back to original english firmware ? I'm from Hong Kong Many thanks