Can't seem to use 5GHz APs with Intel wireless

Hi,

(Apologies if this is the wrong list, please point me at the right one if you know)

I run 12-CURRENT (r334442) on a Thinkpad X230. This machine has an Intel
Centrino Advanced N 6205. But freebsd only uses in in 11g mode. When I
try to scan, it won't even display 5GHz aps.


wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether a4:4e:31:02:70:3c
	inet 192.168.1.108 netmask 0xffff0000 broadcast 192.168.255.255 
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
	media: IEEE 802.11 Wireless Ethernet MCS mode 11ng
	status: associated
	ssid SSID channel 7 (2442 MHz 11g ht/20) bssid bc:8a:e8:0b:a9:3f
	regdomain FCC4 country DE authmode WPA2/802.11i privacy ON
	deftxkey UNDEF AES-CCM 2:128-bit txpower 30 bmiss 10 scanvalid 60
	protmode CTS ampdulimit 32k ampdudensity 16 -amsdutx amsdurx shortgi
	-stbc -ldpc wme roaming MANUAL
	groups: wlan 



>From reading man pages, I can see that iwn(4) supports 11n. Is it
really supprted?  What can I do to enable 11n?


Here are my configs

/etc/rc.conf
wlans_iwn0="wlan0"
ifconfig_wlan0="ssid SSID WPA SYNCDHCP"


/etc/wpa_supplicant.conf
ctrl_interface=/var/run/wpa_supplicant
eapol_version=2
ap_scan=1
fast_reauth=1

network={
ssid="SSID"
scan_ssid=0
psk="PSK"
priority=5
}


/boot/loader.conf
# wifi
if_iwn_load="YES"
iwn1000fw_load="YES"
iwn100fw_load="YES"
iwn105fw_load="YES"
iwn135fw_load="YES"
iwn2000fw_load="YES"
iwn2030fw_load="YES"
iwn4965fw_load="YES"
iwn5000fw_load="YES"
iwn5150fw_load="YES"
iwn6000fw_load="YES"
iwn6000g2afw_load="YES"
iwn6000g2bfw_load="YES"
iwn6050fw_load="YES"