Updating your iPhone to OS 3.1.2 results in breaking the Tethering hack. Wanna get Tethering back? Yes! follow the steps below in order to enable tethering on iPhone OS 3.1.2.
How to Enable Tethering on iPhone OS 3.1.2
You need to Jailbreak your iPhone first.
Go to Cydia and Search for MyWi and install it.
It will also install the Rock app. Don’t worry it’s temporary.
Now launch the Rock app that it just installed. and Go to:
Manage > Rock ID > Create New RockID
accept the agreement and create an account.
Now there you will see an update for MyWi app. Update it. Then it will ask for a soft restart.
Now open MyWi and turn the USB/Bluetooth Tethering options ON. and reboot your Device.
Now go to:
Settings > General > Network > Internet Tethering
and turn Tethering ON.
MyWi is a paid App. You can keep it by paying $9.99.
or
There’s a trick that SSH into your iPhone and delete Rock and MyWi from applications folder. Then ReSpring your iPhone. Even after the reboot, Tethering will be available in your iPhone.
Have Fun with Tethering on iPhone 3.1.2 and don’t forget to leave your feedback and you can also folow us on Twitter.