Because of an apparent bug in the Widcomm WinXP Bluetooth drivers, I decided to try enabling Bluetooth in Linux to give the Tapwave Zodiac wireless internet access.
Linux Bluetooth works great! 
Bluetooth success in Linux is a result of the BlueZ driver project, which is conveniently included with the Kernel since 2.4. Thanks to a huge collection of online documentation, especially from Tills and Ben, getting the Zodiac to connect through my Linux box was mostly a piece of cake.
Apparently, most new distros have Bluetooth support functional right out-of-the-box [mandrakediskswap, mandrake10]. On my older, hand-cobbled Linux box, I did have to patch and recompile my Kernel (2.4.20) and download and compile the latest BlueX utils, iptables, and pppd daemons. But with a one-line change to the BlueZ util source, everything compiled and installed without a hitch.
Finally, I've got the Zodiac on the net without WiFi or GRPS!
