What exactly happens when you try to install the drivers and how are you installing them? As long as the drivers are for XP or 2000 then the modem will be ok.
Don't worry if XP complains the drivers are unsigned or may not be for that modem, install them, try the modem via its tab in the control panel to see if it responds and if it works then fair enough, if not then we can try another driver
Have you tried this driver Coggy?
http://members.driverguide.com/drive...driverid=43296