How to do internet tethering for iphone 3.1.2?

For those of you having problems you must first of all haverock app installed and you must set up an account through the app. Ifinstalling mifi did not already install rock app you can get from yourblackra1n app. after that run mifi and set it up. If for some reason itbroadcasts a signal but will not allow you to connect to the internet on yourPC you must restart your iphone. This is the solution , Go to Settings, Press General, Press Network, Press VPN, Switch VPN on thenoff, Press Add VPN configurations, PressAuto under the Proxy settings, Press Cancel, Go back to main screen , Go to Settings, Press General, Press Network. Your InternetTethering should be back. I did not make any changes, hack the phone ordownload any updates I don't there has been any since 3.1.2 and I gottethering back.