The sundtek doesn't use a driver. It comes with an installer that installs an application (closed source) that communicates between the stick (using low-level USB access) and a vtuner. No drivers involved.
There may be other "proper" wlan sticks usable for dm800, but you need to be very careful if they're supported on a linux 2.6.18 kernel.
Thanks. I leave all at that and maybe I'll buy Amiko Alien 2.