How I got mine to work. Very simple, no need for crazy setups.
1. Set the Initialization command in the "Standard Modem" to:
+cgdcont=1,"IP","wap.voicestream.com"
2. Setup the Dialup Connection as explained earlier to *99#, no uid/pw.
3. Open Desktop Manager software.
4. Dial the Connection!
Also noted that I was able to leave the compression on, and I'm connected at 921.6.