As already stated by me and some forummers, this problem is caused by your Network Provider. Namely Maxis, Celcom, Digi etc. So far only Maxis users complained of such problems. This problem has nothing to do with IOS6.1 or anything. You just need to go to your Network Provider and get your NanoSim replaced. Those who got your your nano sims from them will get it replaced free while those who cut will get charged. So far those who got their nanosims replaced don'tt face this problem anymore.

This post has been edited by TOMEI-R: Feb 20 2013, 10:45 AM

I've changed mine already. And I can tell you the nanosim is the problem. Issue was admitted by Maxis staff and the Maxis centre. After changing the nanosim, no such issues anymore. Apparently this issues only affect some users.

6.1.2 is just a minor update of about 12mb. This is just to address some bug issues with the calendar. Dont think it will bring a lot of difference though.

This post has been edited by TOMEI-R: Feb 20 2013, 11:27 AM

Yes, that is what happens with IOS 6.1. Only after you replace the sim card you can resolve this problem. Same case with all the users here, before 6.1 3G was all fine.

Maxis' Edge is totally doesnt work. I migrated from Digi. Digi has excellent Edge coverage. Thought slow but it is good enough for notifications, whatsapp etc. When I changed to Maxis, I have to keep 3G turned on just to receive these notifications and messages. However I do understand that maybe Maxis has already given up on developing Edge as nobody uses Edge for surfing etc because it is too slow. So have to keep 3G on though it drains the battery. Have to keep the chargers on from now.