Be prepared as I have some good news and some bad news. Good news is
that I can give you the correct settings to use your T809 as a dial up
modem. Here is the settings assuming you are running Windows XP.

Make sure that your phones' USB settings are set to medem not mass
storage.

Once you install the phones software and drivers go to Start/Control
Panel/ switch to  classic view and select "Phone and Modem Options."

USB modem 1.0. Select it and click on its Properties button. From there
click on the Advanced Tab and put this in Exactly as shown in Extra
Initialization Commands. Note there are no spaces in the string of
values below:

at+cgdcont=1,"IP","internet2.voicestream.com"

Click Ok then OK again. once that has saved you should be good to go to
the next step.

Next go to Start/Control Panel/Network Connections and create a new
connection. Do not use the Network wizard that comes with your PC
Studio software as I was unable to correctly configure it. When the
wizard pops up to create a new connection choose Connect to the
Internet. Click next. Choose Set up my connection manually. Click Next.
Choose Connect using a dail-up modem. Click Next. Choose a name for
your connection. I chose T-Mobile. Click Next. Now for the phone #.
Enter this exactly as shown.

*99***1#

Click Next. uncheck the 2 boxes and DO NOT PUT ANYTHING IN USERNAME OR
PASSWORD SECTION. Click Next and finish the wizard. Now once you create
your dial-up connection go to it in your Network Connections.
right-click and go to properties. Make sure that it never waits for
tone to dial and never use a dial-tone. Thats it. your done. Not too
bad ehh? Well here's the bad news. In order to use full capabilities of
T-Mobile's network you have to purchase the TOTAL INTERNET PACKAGE
from T-Mobile which costs a Whopping $29.99USD a month. I know it
hurts, but with T-Mobiles fast EDGE its 3 times faster than regular
dial-up.

Hope this helps,

Project Eden