T-Mobile USA has changed the IP address in their system for the T-Zones service. For anyone on 1.1.4 and below you will have to SSH in and manually change your settings (see below) or upgrade to 2.0+ and install the NEW T-Zones Hack provided by Big Boss in Cydia. For anyone on 2.0+ who has the previous hack installed you will need to update to the new one.
You must subscribe to the $5.99 T-Zones service for the T-Zones hack to work.
"For 1.1.x users that really don’t want to upgrade, you can fix proxy.pac yourself but editing the file /var/preferences/proxy.pac and changing “10.0.0.0″ to “25.0.0.0."