wpasupplicant problems in adhoc mode

[alex]

Hi i'm using wpa_supplicant v0.4.7, when i try to run  wpasup i get this:

wpa_supplicant -c /etc/wpa_supplicant.conf -iath0 -B -Dmadwifi
ioctl[SIOCSIWMODE]: Invalid argument
Could not configure driver to use managed mode

(i'm using madwifi-ng driver at ath0)

The cards seems to works but noone station could autenticate, anyone could 
help ? Regards

this is my configurationfile(that i think all is ok for work in adhoc mode):

ctrl_interface=/var/run/wpa_supplicant
ap_scan=2

network={
        ssid="LDL Labs"
        mode=1
        key_mgmt=WPA-NONE
        proto=WPA
        pairwise=NONE
        group=TKIP
        psk="xxx"
}