mediaopt turbo wedges ath0

I have a Netgear WG311T (ath driver) and trying to get it into "turbo"
mode wedges the card.  This is consistently reproducible on my test
machine.

# kldload if_ath
ath_hal: 0.9.14.9 (AR5210, AR5211, AR5212, RF5111, RF5112, RF2413)
ath0: <Atheros 5212> mem 0xe3800000-0xe380ffff irq 7 at device 9.0 on pci0
ath0: [GIANT-LOCKED]
ath0: Ethernet address: 00:09:5b:c8:19:69
ath0: mac 5.6 phy 4.1 radio 1.7
# ifconfig ath0
ath0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
        ether 00:09:5b:c8:19:69
        media: IEEE 802.11 Wireless Ethernet autoselect
        status: no carrier
        ssid ""
        authmode OPEN privacy OFF txpowmax 100
# ifconfig ath0 mode 11g mediaopt turbo
# ifconfig ath0 up
ath0: unable to reset hardware; hal status 3
#

The card is then unusable until I reboot.  Unloading and reloading the
module doesn't bring it back to life.

I'm running 6-CURRENT as of right after sam_at_'s commit of:

  src/sys/net80211/ieee80211_node.c 1.42
  src/sys/net80211/ieee80211_output.c  1.18

Am I doing something wrong?  If this isn't a known problem, is there
anything I can do to provide more information as to what's going wrong?

	--Emil