I have tried to flash evo 4G's rom, just failed silently, return to fastboot without any message.
Also, factory reset just return to fastboot, with message security warning.
Fastboot -w just said remote not allowed.
So, maybe my only option is to wait ICS RUU... my God!
Anyway, thanks very much, especially to unknownforce!
If so, re-unlock, then try to flash the RUU or factory reset again.