For all the people using this USB card, there is a new version of the driver. For more information check this link: http://www.linksysinfo.org/modules.php?name=News&file=article&sid=320

Please note that this drivers is for version 4 of the card. It will not work with version 2 (I tested this). I do not know if this one works with version 1.

If this new version does not works for you, use the former version of the driver: ftp://ftp.linksys.com/pub/network/WUSB54Gv4_20050321.exe

Info about this file: http://www.linksys.com/download/vertxt/WUSB54Gv4_Release_Note_20050321.txt