How To Use Your GSM Cell Phone as a Bluetooth Modem on Mac OS X

What you need:

A Mac with Bluetooth. Get a Bluetooth USB Adapter if your computer doesn't have built-in Bluetooth.
Mac OS X,v10.3 Panther or at least v10.2 Jaguar.
A GSM phone that supports Bluetooth (e.g. Sony Ericsson T68i or T610).
An Internet Service Provider (ISP) dial-up account, e.g. EarthLink,
or
GPRS data service from your cellular provider, e.g. T-Mobile's T-Zones option.

Dial-Up Account vs. GPRS Service

With most GSM phones, you have two ways to get online. The first is to use your cell phone as a traditional analog telephone modem. You'll use voice minutes from your existing cell phone service plan, and you'll connect using a standard PPP-based ISP dial-up account, such as EarthLink. This approach is slower and less reliable, but costs nothing extra if you already have an ISP account.

The second is to use your cellular provider's GPRS service. Since GPRS is a digital data service, you don't connect through analog modems, so both connection and data transfer speeds are faster. If you've subscribed to WAP service ("wireless web") on your cell phone, you may already GPRS enabled; however, most providers charge by the amount of data transmitted per month.

	Dial-Up Account	GPRS Service
Cost	$21.95/month (EarthLink)	$3–10/month (T-Mobile)
Charged By	Time (voice minutes)	Data size (MB transferred)
Speed	Slower (~9600 bps)	Faster (~33.6 Kbps)

First-Time Setup

1. Download and install a modem script for your phone if necessary.

Dial-Up Account

GPRS Service

Mac OS X ships with modem scripts for some cell phones, including the Sony Ericsson T68i/T610. Check if you already have the modem script you need.

Open Library -> Modem Scripts.

If not, download and install the necessary

Drop the new modem script(s) into Library -> Modem Scripts.

Mac OS X doesn't ship with any GPRS scripts.

Download and install a GPRS modem script for your phone.

Drop the new modem script(s) into Library -> Modem Scripts.

2A. Use the Bluetooth Setup Assistant to set up your phone.

Open Applications -> Utilities -> Bluetooth Setup Assistant.
Select the "Mobile Phone" device type.
Complete the pairing process.
Select "Access the Internet."

Dial-Up Account

GPRS Service

Choose "Use dial-up connection."

(No, don't choose "Use data connection," even though you're using GPRS.)

5. On the next panel, enter the necessary information:

Dial-Up Account

GPRS Service

Enter the Username, Password, and Phone Number for your ISP account.

Choose the appropriate modem script for your phone.

Leave the Username and Password fields blank.

If you use T-Mobile's T-Zones, enter

o Phone Number: wap.voicestream.com

o Modem Script: Ericsson GPRS CID2

Otherwise,

(Yes, enter an Internet address as the "phone number.")

2B. Use the Bluetooth and Network system preferences to set up your phone, using the settings described above.

Usage

1A. Use Internet Connect to establish a connection.

Open Applications -> Internet Connect.
Select the Bluetooth pane. (On Panther, make sure the "Main Number" configuration is selected.)
Click Connect.

1B. Use the Modem menu extra to establish a connection.

If you don't see this menu, go back to the "Modem" tab of the Network preference, and select "Show modem status in menu bar."
Make sure Bluetooth is selected in the menu.
Choose Connect.

Troubleshooting

"Could not open the communication device." Make sure your phone is correctly paired with your computer. Make sure your computer has Bluetooth installed and enabled.

"No carrier detected. Please check phone line connection and try again."

Use a different or slower modem script. I got the Dial-Up method working with the "Ericsson T39 14.4" script, but not with the faster 19.2 and 28.8 scripts.
On Panther, make sure you're setting the modem script in the right place. The "Main Number" configuration of Internet Connect corresponds to the "PPP" tab of Network preference. Other configurations in Internet Connect can be set to other modem scripts.
Make your phone rescan for networks. (On the Sony Ericsson, choose Connectivity -> GSM Networks -> New Search.) Or, just turn off your phone and turn it back on.
You can try fiddling with the "Wait for dial tone before dialing," "Send PPP echo packets," etc. settings, but this should not be necessary if you're using a proper modem script.

"The connection has failed. Please verify your settings and try again." If you're using GPRS, change your modem script to a different CID number and try again.

"No answer from the remote site. Please verify your phone number and try again."

If you're using GPRS, make sure you're within range of data service. Try browsing the web on your cell phone. Contact your cellular provider for support if GPRS does not work.
Make your phone rescan for networks. (On the Sony Ericsson, choose Connectivity -> GSM Networks -> New Search.) Or, just turn off your phone and turn it back on.