Encountering the same issue. It runs well within the 3G coverage in Msia but after it disappears, it will not come back on, meaning stuck without 3G. The phone needs to be manually reboot in order to get the 3G back, same place with my ip4 has full bar !!

I am wondering if IOS or iphone5 is screwed up or our local telco supplier/ MAXIS screwed up?

When call them, they say Apple fault as it is software/ IOS related .. Rather sickening to turn on/off just to get a stupid 3G signal, which i am paying for .. sometimes, wondering would the Kimchi competitor better...

IOS 6.1.3 solve the the problem?

I am using 6.1.3 already .. Thought it wud improve but looks the same to me. I dont mind, getting 3G on/off .. but wht piss me off is it doesnt search n reconnect 3G after it goes missing for sometime.

yup