Comment 1 for bug 53387

What worked for me (I have an atheros chipset, using madwifi) is a /etc/wpa_supplicant.conf like this:

ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=0
eapol_version=1
ap_scan=2
fast_reauth=1
network={
        ssid="YOUR-SSID"
        proto=WPA
        key_mgmt=WPA-PSK
        pairwise=TKIP
        group=TKIP
        psk=(fill in this using wpa_passphrase)
}

And a wpa_supplicant start up script in /etc/init.d like this:

#!/bin/sh
# wifi wpa_supplicant init
echo "* [Wifi] enabling wpa_supplicant..."
if [ -x /sbin/wpa_supplicant ]; then
        /sbin/wpa_supplicant -B -c/etc/wpa_supplicant.conf -iath0 -Dmadwifi -w
fi

You then have to:

sudo chmod +x /etc/init.d/wifi_wpa.sh (or whatever you called it)

sudo ln -s /etc/init.d/wifi_wpa.sh /etc/rcS.d/S40netwifiwpa

Yes, this should probably be automated.