Same problem here. First rooted and then installed another rom and now it says only emergeny calls.
I have upgraded to kitkat though. but still no recognizing of a provider. It says when i want to call : not registered to a network.
1 minute ago i did register to a network but still the same.
Familiar to anyone ? Thanx for the help.
One thing still....
I did use KIES and installed 3 times the stock rom of the S3 before rooting and installing a kitkat new rom.
Still not registered to a network and of course only emergency calls.