please let us know what firmware that u have restored to.

i assume that ur phone is lock again (where only emergency call is allow)

you need to unlock/jailbreak/activate it again either using winpwn (firmware 1.* to 2.0.2) or using quickpwn (2.0 to 2.2)
follow the step given on the pinned topic http://forum.lowyat.net/topic/790913

cheers