iwconfig Bit Rate for 802.11n 40Mhz

[Curtis Larsen]

Hello,

I am using  wpa_supplicant 0.7.1, ubuntu 10.04, Atheros AR9280.

When I connect to an 802.11n *20mhz* (channel 36) SSID and do
"iwconfig" I get the following output:

wlan2     IEEE 802.11abgn  ESSID:"WIFI"
          Mode:Managed  Frequency:5.18 GHz  Access Point: 00:26:CB:90:7B:B0
          Bit Rate=156 Mb/s   Tx-Power=30 dBm
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=49/70  Signal level=-61 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

When I connect to an 802.11n *40mhz* (Channel 36+40) network and do
"iwconfig" I get the following output:

wlan2     IEEE 802.11abgn  ESSID:"WIFI"
          Mode:Managed  Frequency:5.18 GHz  Access Point: 00:26:CB:90:7B:B0
          Bit Rate=0 kb/s   Tx-Power=30 dBm
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=46/70  Signal level=-64 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

...The Bit Rate is always "0 kb/s".  How can I get iwconfig (or
perhaps another linux CLI tool) to display the correct Bit Rate when
using 40Mhz wide channels?

Thanks,

Curtis