Linux: Atheros wifi can't see channels 12 and 13

Google Fodder: I had set my D-Link 624S wifi router to automagically select the channel with the least interference. It opted for channel 13. That was cool with all my systems except my laptop (Acer Travelmate 2483 with Atheros wifi chipset).

Googled around and found the bug on Launchpad. The key piece to sorting this out was adding this line to my /etc/modprobe.d/options and then re-starting my system (simple - brute force!):

options cfg80211 ieee80211_regdom="EU"

"iwlist wlan0 channel" previously only reported channels 1 to 11, but now shows all of them. No problems connecting to the AP now on channel 13:

steve@steve-laptop:~$ iwlist wlan0 channel
wlan0 13 channels in total; available frequencies :
Channel 01 : 2.412 GHz
Channel 02 : 2.417 GHz
( blah blah blah blah )
Channel 11 : 2.462 GHz
Channel 12 : 2.467 GHz
Channel 13 : 2.472 GHz
Current Frequency=2.472 GHz (Channel 13)