I everybody, I need your help, I think I made a Mess:

My iPhone originally was 1.0.2, firmware 03.14.08_G, unlocked and jailbroken.
I have tried the update to 1.1.2 from iTunes 7.4 (on a pc), dowgrade to 1.1.1, jailbreaked and ri-upgraded to 1.1.2.
Now I cannot jailbreak the 1.1.2, the firmware shows 04.02.13_G and iTunes does not want to recognize the iPhone, it tells me that it could be damaged and to take it back to Apple!
The phone is working, I mean it lets me make the emergancy calls, but that's about it.

Do any of you ever had anything similar?

what do you think it might have happened?

Thnsk for your help,