urtw(4) disconnect problems

Hi,

I'm having problems with frequent disconnects of my AirLive WL-1600USB
hardware. After this happens the all reconnects fail and the only way
to fix it is to reboot the machine, while reboot I get this kernel
panic:

http://people.freebsd.org/~pawel/urtw-panic.jpg

Sadly when I get to this my USB keyboard is non operational anymore.

My system:
FreeBSD blaviken.slowicza.org 10.0-CURRENT FreeBSD 10.0-CURRENT #30
r254760M: Sat Aug 24 10:24:42 CEST 2013
corn_at_blaviken.slowicza.org:/usr/obj/usr/src/sys/BLAVIKEN64  amd64

Disconnect errors part of dmesg:

wpa_supplicant[1382]: wlan0: Authentication with bc:ae:c5:c4:8c:98 timed out.
wpa_supplicant[1382]: wlan0: CTRL-EVENT-DISCONNECTED bssid=bc:ae:c5:c4:8c:98 reason=3 locally_generated=1
wpa_supplicant[1382]: ioctl[SIOCS80211, op=20, val=0, arg_len=7]: Can't assign requested address

-- 
pozdrawiam / with regards
Paweł Pękala