I have exactly same problem. I think the GSM radio is bust... I ordered new mother board after many attempts at flashing, repairing...
Will report when I get it,
SE T68, Casio E200 -> Great
SE P800, iPAQ 3970 -> Amazing
SE T630 -> Stolen
HTC JasJar -> Incredible, but needs a new M/B
HTC Artemis -> Cute and Furry!
HTC Polaris -> Didn't connect to...
Samsung Omnia -> Nimble little phone
HTC G1 -> Linux in my hands...
Omnia B7610 -> Power in my hands...
Beam -> I can see the light!
HTC HD2 -> Big and Bad
Atrix4G -> NVIDIA in my pocket (!)
Evo3D -> Opened my eyes 8)