Yes, but I _think_ (not an expert though), you will have to flash the card. Instead you will have to be in "Ad-Hoc Mode" which one permit to clients to talk together without a base. But this mode doesn't support stats so no signal strength and so on... But I'm sure it's doable...
As a datapoint, I set my old (PowerPC) laptop up as a basestation using an Orinoco gold card. It runs in Ad-Hod (iBSS) mode, and the other computers are in managed mode. I *do* get link quality indications on the client PCs (a TiBook w/Airport and a B&W G3 with a Skyline PCI card).
I've had good luck with the Airport under Linux, except for once in a blue moon when it'll decide that eth1 no longer exists, and nothing I can do can convince it otherwise, so I have to reboot.
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Wilhelm Fitzpatrick | When we speak of free
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