Configuring Dial Up Networking
Open Bluetooth Preferences by navigating to System Preferences -> Bluetooth.
Click on the Advanced button.
Bluetooth-PDA-Sync and SerialPort should display. If not, click the + button to add SerialPort.
Open Network Preferences by navigating to System Preferences -> Network.
In Network Preferences, Select Bluetooth DUN and click Add Configuration.
Name the configuration Blackberry.
Under the Blackberry configuration, enter *99# for the Telephone Number.
Enter your Blackberry's phone number preceded by a one (e.g. 13125553412) for the Account Name.
Enter your T-Mobile password (i.e. the password you use to login to your account online) for the Password.
Click the Apply button and then click the Advanced button.
On the Modem tab, select Research In Motion as the Vendor.
Select BlackBerry IP Modem (GSM) for the Model.
Enter epc.tmobile.com for the APN.
Click OK. In Network Preferences, select Bluetooth DUN with the Blackberry configuration and click the Connect button to tether.
Browsing seems pretty peppy when I am tethered to my phone, which leads me to believe that I may be taking advantage of the 3G capabilities of my phone. I have, however, not monitored my network speeds while tethered.
For quick access to Bluetooth devices and Dial Up Networking, I put both Dial Up Networking and Bluetooth Preferences in the Menu Bar.