I have just received a new Z8, it has the Orange carrier menu, SIM-Lock removed, however, it has a major problem, every time I close the keypad the phone turns itself off, then when I open the keys I need to turn the phone back on to use it, this is annoying as hell and I don’t believe it was meant to work this way, please I’ll welcome any suggestions …. The battery is good; the power cable is good; I have no clue what to check for….
I had the same problem when I picked up my phone (used). I see that the thread is a few weeks old but I will pass my fix along.
Turn the phone off
Fold a small piece of paper up and use it as a shim to keep the battery tight to the case (towards the contacts)
Fold another one to keep the battery against the phone ( between the phone and the battery cover.)
Give it a try. mine has been good sine I did that.