If you want to access the internet via your phone 3G/GPRS connection you can use Bluetooth PAN. In my case I have a Sony Ericsson W715 so the first thing to do is to tell the phone which connection to use Menu > Settings > Connectivity > Bluetooth > Data accounts and select the account that you normally use to browse the net from the phone.

Then turn on bluetooth

Then in the mac:

1. Go to System Preferences > Bluetooth

   

2. Set up new device.

   

3. Set up a new device
4. Click on continue

   Then a screen will appear with a passcode that you have to enter in your phone to do the pairing. if the phone ask you if you want to start the remote control say yes.

   

5. In the next screen enter your phone model and apn in my case its online.telia.se and he cid i used 5 because i think itsd unused

   

   See summary and click quit

6. Go to System preferences > Network
7. There is a "Bluetooth PAN" already but that one won't work: you need to create a new connection

   Press the “+” in the bottom left corner. Set the interface to “Bluetooth PAN” Set the name of the connection to whatever you like. I just typed “W715” in my case.

   

8. Turn off Airport or any other connection that you may be using and the go to your newly created connection and click on "Connect"