with odin, from 2.2.1 to 2.3.4 or 2.3.5 i don't remember exact.
i removed the battery and then it worked to enter download mode.
then i updated to stock flash XXJVT and when it had to restart.. it didn't, although odin said everything is passed!
the screen remained black. battery was full and process took 3minutes.
I removed the battery and tryed to enter any mode, download, restart, safe mod, but nothing works. Also, it can not be recognized by pc or by charger.