For chinese 003 phone, I would keep in 003 line and just change language from UI from chinense to english. Thats the only way to keep cmt (and sim-card working).

I suspect that the other phone has been 003 originally and someone has just tried to flash random firmware in it (that would explain non-working sim). So thats more trickly one, basicly if it has been 003 and someone has flasher some newer non-003 firmware in it, then you will never get sim working, ie you have wifi-tablet or brick in your hands. But if your lucky and it has not been 003 chinense from beginning, then you might get lucky by reading this forum.