iwn0/wlan0 scan WPA2-PSK/AES as WEP on freebsd9

[乔楚/HonestQiao]

I have a lenovo thinkpad x201i which os is FreeBSD9.1-prerelease/amd64.
Its wireless card is Intel Wireless N-1000, and driver is iwn/iwnfw.

And I have an home wireless route which is TP-LINK TL-WR843N.
When I set WR843N as WPA2-PSK/AES mode, my BSD can't connect to it.
Set: 2.4G / 11bgn mixed / 40MHz / chl:11 / 300Mbps 
#ifconfig wlan0 down
#ifconfig wlan0 up scan
#ifconfig wlan0 list scan
It will list WR843N as a WEP AP, so it cant connect to AP.
But other laptor which os is windows7 can connect to AP correct.
And My MobilePhone which os is android 4 can alao connect to AP.

When I set WR843N as WEP mode, my BSD can connect to it.
And I can connect to my company's WorkStation AP which mode is WPA2-PSK/AES.

Other info:
My BSD cant get right AP name of my WR843N.
The name of WR843N is 0x................
Other electronic devices can get it correct.

I also use the script named wifimgr in install iso of freebsd9, and use wifimgr in ports.
But the results obtained are identical.

Any one can tell me how to debug it, or force My BSD to correctly recognized WPA2-PSK/AES mode of WR843N?

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HonestQiao/乔楚 
http://www.coreseek.cn/ 
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