Default Enabling 3G Network Only

For users who are unsure on how to enable 3G network only, here's a guide for you!

Step 1: Tap on “Phone”.
Step 2: Dial “*#*#4636#*#*”.
Step 3: Select “Phone information”.
Step 4: Select “Set preferred network type”.
Step 5: Select “WCDMA only”.

Taken from http://droidbar.net/2010/10/how-to-e...-network-only/