I'd like to continue this post.. but I discovered it's archived... anyway.. my problem is quite the same with some differences.

At home with my MacBook I'm able to use from BT4 virtualized using ParallelDesktop my USB WIFI AWUS036H card. I've first set up all the drivers into MAC OS and only after that they were available to let ParallelDesktop (and so BT4) use my USB WIFI card.

At work I'm on Xp and virtualizing BT4 on VMware Server (2.0.1)
hxxp://img80.imageshack.us/img80/8172/bck20091112150310.th.jpg

While BT4 was down I've plugged in the WIFI USB card and then detacched it from WinXp. Then I started my BT4 virtualized machine and the following images are what I see on the bottom of VMware window:
hxxp://img91.imageshack.us/img91/9197/bck20091112150042.th.jpg

hxxp://img402.imageshack.us/img402/5323/bck20091112150050.th.jpg

The following images are what I see on the top of VMware window:
hxxp://img156.imageshack.us/img156/821/bck20091112150119.th.jpg

hxxp://img441.imageshack.us/img441/2105/bck20091112150132.th.jpg

lsusb:
hxxp://img91.imageshack.us/img91/7641/bck20091112150158.th.jpg

What Am I missing on Xp?

Thanks for your support

Solved...

In vmware server 2.x you have to select your guest machine (that is also already running) and then from the USB controller menu in the toolbar, select the device you want to connect to in the Plugged into Host list as the following image.

hxxp://img8.imageshack.us/img8/7317/bck20091113110644.jpg

Hope this could be helpful for somebody else