Try to stop whatever's using it.. maybe "iwconfig ath0 down" might work.Correct code appears to be "ifconfig ath0 down" for deactivating the card. That still doesn't stop getting "device busy" when typing "rmmod ath0," but perhaps removing the module is not neccessary for next loading the MadWifi drivers and getting the card working using iwconfig. I tried it and it worked, although for some reason now even the default drivers are working, so I can't tell which drivers are loading. Go figure!
Thanks for the suggestion.rmmod is used to remove modules. rmmod iwconfig doesn't make sense. Neither does rmmod ath0. iwconfig is a program/utility. ath0 is a network interface.