I got an unlocked iPhone 4 and signed up for the new plan on T-Mobile. Everything worked, except for the Mobile Hotspot/Tethering. I called tech support, and they had me change the APN to pcweb.tmobile.com. He also said that I would have to up my plan from the 500MB plan to the 2.5GB plan. I did that. He said it would work in a few hours. It still doesn't work.
What else do I need to do in order to get Mobile Hotspot working.