Form my notes when I did this a few days ago. The situation is that the SME 7.2 seems not to have the Atheros kernel module, so you will have to install it. By the way it did not work completely like it should when I tested it. It was some hardware adressing conflict, but I guess it was related to my hardware only (??). I would be courious to know if it works on your PC.
1. Installed a development environment to the SME 7.2 server.
2. Downloaded madwifi sourcecode from madwifi.org
3. Unpacked and navigated into the unpacked download area.
4. Runned command: make
5. Runned command: make install
6. Loaded kernel module: modprobe ath_pci
Then everything looked ok when i ran "ifconfig ath0 up", and "ifconfig ath0", but I could not make it work properly.
Looking at the messages when the PC booted I could see that there were some message when starting the eth0 when the Atheros card were physically installed. (That's the reason I guessed It was some hardware adressing conflict.)