Special thanks to Grant Goodale for his work in putting together these modem scripts in Leopard form and distributing them freely. If you find this script useful then please don't thank me, thank him. He has a paypal donation link on his page if you are feeling generous.
Here's how you set it up:
(Note: use the APN in the phone number field)
# APN: wap.cingular
# Username: ISP@CINGULARGPRS.COM
# Password: CINGULAR1
It can be helpful for making quick connections to your blackberry if you enable the checkbox next to "Show modem status in menu bar."
If you have a BlackBerry 8700 from a different wireless carrier, then you might try some of these other carrier-specific settings.