[nehuenmingote]

Hi ppl! I'm desperately seeking for some guidance.
A few nights ago I launched Cydia in my iphone 3G (jailbroken OS 3.0 a week ago) and allowed a requested update to start (can't quite remember which app was). Immediately after updating, my iPhone freezed so I restarted it, but when doing this, it freezed on the Apple logo. I restarted several times without success. I decided to restore my iphone, and could only do this after several attempts. Since then, I get the "searching..." and "no service" in the carrier tab (still not jailbroken, so it wasn't due to jailbreak activation distraction). I tried repeating the restore, but nothing changed. The most curious thing is that I inserted a friend's sim card (from the same carrier: Movistar Argentina) and it worked smoothly.
Is it possible that the Cydia update ruined my Sim card?
Thank you very much for the replies!