It's damn easy (depending on your phone )
If you got a Windows Mobile Smartphone (like HTC, etc.), start Internet Connection Sharing and select to share it via bluetooth.
Enable bluetooth on the Pandora as well and create a connection between them (the Pandora will show you a number which you have to enter on the phone. Only needed for the first time you connect your phone with the Pandora).
In the last step of the bluetooth connection setup on the Pandora, there will be a small box which says that it should use the phone for internet connection. Tick this!
Finally, once the connection is established, there's a PANU device in the network manager. Connect to that and you got mobile internet