How to enable EDGE / 3G from the list of supported carriers.
See below for the list of supported carriers.
If you have an unlocked iPhone and would like to use cellular internet access on the network of a carrier that is not the one who originally sold the iPhone, please follow the instructions.
1. On your iPhone, in Safari, open the address : http://www.disable3g.com.

2. When asked, enter your unique access code and tap 'Enter'.

3. On the welcome screen, tap 'Browse List of Carriers'.

4. Scroll down until you find your carrier. Tap on the carrier's name.

5. A new window will pop-up, tap 'Install'.

6. A confirmation box will pop-up, tap 'Install Now'.

7. When it is done installing, tap 'Done'.

That's it, you have successfully enabled cellular internet access on your iPhone via EDGE or 3G. NOTE: Check cellular internet access rates with your carrier. It can be very expensive if you don't have a data plan.
To go back to your original settings
1. On the home screen on your iPhone, tap 'Settings'.
2. When the Settings window has opened, tap 'General'.

3. On the 'General' settings window, scroll down to the bottom and tap 'Profile - Enable EDGE / 3G'.

4. The details will be displayed. Tap 'Remove'.

5. A confirmation box will pop-up, tap 'Remove'.

That's it, you have returned your iPhone to its original EDGE / 3G settings.
Supported Carriers
AT&T (VPN) - USA
AT&T - USA
Cellular One - USA
Cincinnati Bell - USA
T-Mobile (Internet) - USA
T-Mobile (VPN) - USA
Rogers (Internet) - Canada
Rogers (VPN) - Canada
Fido - Canada
Optus - Australia
Telstra - Australia
Three - Australia
Vodafone - Australia
Jersey Telecom - UK
O2 UK (contract) - UK
O2 UK (prepaid) - UK
Orange UK - UK
T-Mobile - UK
T-Mobile (One2One) - UK
Vodafone UK - UK
