Only the newest (7.82.0.550) Sat1800 driver has support for WPA, but the only site it was hosted on (agere.com) seems to be taken over by some spammers.

Support Information:
Device Type: Network Adapter
Manufacturer: Toshiba
Model: Wireless LAN Mini PCI card
Interface: Other
Operating System: Windows XP Home
Age of Device: Not specified
FCCID:

Find it on DriverGuide (http://members.driverguide.com/index.php?action=srch&sm=b&aax=&qa6=1066&qa5=12&qa7=1500&dp=3&qm0=Wireless+LAN+Mini+PCI+card&jmd=and&fzz=d) | Find it with Google (http://www.google.com/search?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=Toshiba+Network+Adapter++Wireless+LAN+Mini+PCI+c ard+Windows+XP+Home+) | Research manufacturer Toshiba (http://members.driverguide.com/index.php?action=getinfo&companyid=1066)

Your hardware description is too vague. Please give us something to work with if you expect help.

a valid model number?
what pc system did it come pre-installed in or is it an add-on retail product?

And what is "Sat1800"?

You people think we're mind readers or have magical powers to see through the internet to eyeball your hardware? We can't.