Mac mini intel uses ath0 cards as well as some netgear cards so if it works on them it should on your wifi card as well.
Think we fixed this in loop3 or 3.4a about , also if the firmware depending on the version of sabayon you have is not yet working try the "ndiswrapper + windows drivers" to get it to work and later switch to the firmware driver.
See the networking part of the forums there is a sticky "before 3.4e ipw3945 ....." or something in the name ans this has the ndiswrapper + .inf install ways + tricks not the modprobe ndiswrapper -r 3 or more times then modprobe ndiswrapper if doing it this way.
See also the wiki search:http://wiki.sabayonlinux.org/index.php? ... eros&go=Go