3G Network not working on specific iPhone 3G

[userblah]

Hi, I'm trying to work on a friend's iPhone 3g.

His Edge Network connection works.
His 3G Network connection does not work.

On my iPhone 3G I receive a 3G Network connection without any problems.

When I turn on his 3G his shows signal and the 3G icon.
When I go to Safari it returns saying safari cannot load page because it needs a network connection.
If I try to use safari with 3G turned off (using edge) it works without a problem.

Any ideas on why this would happen?
I have already tried a reset and that did not work.

Thanks,
Matt