I am still having a battle with O2 trying to get some sense out of them. At the top of the contacts screen where the box says, "My Number" mine says "Unable to read from SIM". If I go to settings, about phone, status, my phone number, this says "unknown". My wife has exactly the same phone but on O2 pay as you go. If I put her SIM in my phone, the phone reads the SIM ok and shows the number. If I put my SIM in her phone, her phone cant read the SIM. All the functions work on the phone and apart from these two issues the phone is fine. O2 have sent me 3 SIMS but it has made no difference, my number just doesnt show. I phoned O2 again the other night and was told, "The Xperia X10 is unable to read the number on any contract SIM, but it can read them on pay as you go". I asked if this applied to all networks and was told, "This is a design fault of the Xperia X10, it just cant read any contract SIMS, no matter what network" I know people who have this phone on contract with Orange and Vodafone. Their phones display the SIM number perfectly ok. I dont know anyone with an X10 on O2 contract, but if anyone on here has one, can you tell me if your phone number shows? I want to take this further with O2 but need to know if they are talking rubbish or not!