Downgrading firmware -> Yes (降固件,可以)
Jailbraking -> Yes (with downgrading to 1.1.1 or 1.0.2 first) (解系统 ,可以)
Activate -> Yes (with downgrading to 1.1.1 first ..) (激活 , 可以)
Unlock -> no !! (解锁, 不行!!,打不了电话,只能当iTouch用)
even you downgrade the firmware to 1.0.2, the baseband will stay at the new one. You still can't erase the baseband to make the phone unlockable, since the new 1.1.2 iPhone OTB comes with new bootloader, which looks like it make the bb writer unworking .. (因为1.1.2的新BB(modem)搞不掂)
That's the pain .. (大家都很伤心)
so .. what i was trying to say is .. we can't rewrite bb since the new bootloader arrived .. (等吧,等牛人搞出办法来)