I had some trouble configuring the Wireless card to work on my Toshiba Satellite with its Atheros AR242X wireless card. So, I'm going to spell it out here for the others who run into the same trouble. Basically, as I know it from looking around on the Internet, there are two ways to fix this issue. Either use the madwifi non-free driver or the ath5k free driver.

1. Make Sure madwifi driver is deactivated:

System->Administration->Hardware Drivers DeActivate Alternate Atheros "madwifi" Driver

2. Install linux-backports-modules-jaunty:

$ sudo apt-get install linux-backports-modules-jaunty

This contains the ath5k driver.

3. Ensure that /etc/modprobe.d/blacklist-ath_pci.conf contains the line:

blacklist ath_pci

This ensures that the madwifi driver doesn't interfere with the ath5k driver.

4. Restart networking with:

$ sudo /etc/init.d/networking restart

Hope this helps!!!