Even though new iPhone OS 3.0 software update is released and many users have already upgraded their iPhone to OS 3.0 still some features like 3g tethering, MMS & Push notifications are still blocked.
We have written guide for enabling 3G tethering and MMS on iPhone OS 3.0 GM which is still applicable for final iPhone OS 3.0 software update however that guide requires you to install and uninstall different versions of Apple iTunes. Here is yet another simplest way to enable 3G internet tethering on iPhone OS 3.0.
BenM.at is hosting TONS of iPhone tethering configuration files for many networks across various countries. Simply browse to help.BenM.at/help.php via Safari on your iPhone 3G 3.0. Check out below images for how to enable tethering via iPhone Safari.
Visual Guide to Enable 3G Internet Tethering on iPhone OS 3.0
Open help.BenM.at/help.php in iPhone Safari
Select Install Now
That’s it, Now just browse to Settings->General->Network->Internet Tethering->On and you have tethering.