Mine

modules=( "!iwconfig" )
modules=( "!wireless-tools" )

config_eth2=( "null" )

mtu_wlan0="1492"

modules=( "wpa_supplicant" )
wpa_supplicant_wlan0="-Dwext -c/etc/wpa_supplicant/wpa_supplicant.conf -W -B -iwlan0 -P/var/run/wpa_supplicant-wlan0.pid"
associate_timeout_eth0=5

modules=( "dhcpcd" ) # to select dhclient over dhcpcd

config_wlan0=( "dhcp" )