Reason: Maybe you think it is Apple's problem, in fact, it is not so, the reason is that mobile to hide this function, as for why, must be afraid of others congratulate the network affect their business. The IPCC file has an Apple-made signature, so you just have to change a little bit of information, so it's not working, so we can't add features and let our phone support personal hotspot, you can only pray for the mobile to be kind, but IOS6 move is no matter, so don't wait. Solution:
since know who is the mischief, then say, delete the mobile network configuration file is OK, delete /system/library/carrier bundles/iphone under the CMCC _CN. bundle file, restart Iphne, and you'll see a more shared APN in the APN option.
Perhaps you will ask, deleted the mobile file that is not unable to surf the internet, in fact, it is not so, there is a configuration file and mobile configuration file, it is unknown.bundle This is unlocked iphone configuration file, Inside the support card is the same range and mobile, and more, just like this after your mobile phone operator will show the China Mobile If you can endure, then you can use, if not okay, over a period of time your phone will prompt, whether update operators, updates, Chinese mobile and back, Just a personal hotspot is gone.
iphone Mobile card Manually open personal Hotspot method (for IOS6 need jailbreak)