I did do a fresh re-install of Windows XP Home, but did make a backup of the old one first.
I was not able to find any driver for this usb-wifi-stick.
So I have searched in the backup I had made.
Found this inf file (c:\windows\inf) and the sys file (c:\windows\system32).
Unfortunately for the Win98SE/WinME users, I am missing WlanUI9X.sys
But this driver works great using WinXP (should als work with Win2000).
The end-user of the pc which I re-installed says this stick came with his wifi-modem, a Wanadoo-Live-Box (the Netherlands).
I hope I can help someone else with this (hard-to-find) driver.