winmodems are a little tempermental it would be better to get a hardware modem. that would be an external or internal modem that uses a comport but provides all the activity itself, using none of the cpu's resources.
if this sites driver don't work
http://www.linuxant.com/drivers/hcf/full/downloads.php
then you might try this:
however, check /proc/pci to see if it's seen by the os and just not configured properly. you'll see things like the ide controller, buses, network cards, and such. the modem may or may not be show up as the manufacturers type. if it's listed then write down the IRQ and the IO address from the file. You'll need that to set up scripts to recognize the modem. if it can be done at all.
also you can check the Hardware Browsers in the system tools menu, to see if it's alread seen by the system.
if you see it there it will tell you what port it's assigned to. to use it you must create a symbolic link for some programs . that would be done with the following command.
somesystem@localhost dev] ln -s /dev/ttySX modem
this will set up the symoblic like to the port identified by ttySX, the X being the actual port number.
good luck.