In the browser->menu->options->connection should be set to automatic.
If it has Internet or WAP, I am guessing it has WAP and that is why T-Zones works but not Internet.
Or it could be the other way around, uncheck the automatically detect setting and set the selection to WAP.
Also, you should make sure that you have the WAP to HTTP proxy setup.
And I am sure you must have followed
this setting or similar.