I'm writting a new post based on a little bit more investigtaion. The 
first one seems to
have been eaten up by the mail system, and perhaps this will unplug 
things...

I have compiled both the 2.0 release kernel with the Atheros driver, as 
well
as the 'current' as of around 25 Dec. Both seem to cause the system to 
basically
reboot without too much in the way of a kernel panic or similar.

The sequence seems to be:

ifconfig ath0 mode 11a
wiconfig ath0 -D

The intent is to get a listing of available APs operating in 11a mode.

Just issuing 'wiconfig ath0 -D' seems to only list the b/g APs.

Further if I perform the following:

ifconfig ath0 mode 11a ssid myAP
ifconfig ath0 192.168.3.100 up

Things seem to work ok.

I'll be looking into this as time permits over the next few days.

John