That had me kicking myself for ages when I got my eee too !
I was always rebooting thinking to myself.. this can't be right..
So after you are done using the monitor mode and want to get back to managed for a connection, first destroy ath0;
orCode:airmon-ng stop ath0
then to get it back in managed modeCode:wlanconfig ath0 destroy
(sta = managed)Code:wlanconfig ath0 create wlandev wifi0 wlanmode sta
the ath0 interface will then be created, but is not yet 'up'
so when done inputting your info in iwconfig or wpa_supplicant
Code:ifconfig ath0 up