Unhappy [Q] please inserted SIM card and restart your phone

Good evening I had a problem with my phone sony xperia X10i when I installed 2.3.3 GB ROM, all the tools and applications work well (wifi, bluetooth ..) a small problem on networks, a message appears on screen phone: inserted a SIM card and restart your phone.
But his card works well, I tried the other card I find the same problem.
Please help How to solve the problem?? And how it ??