crda defaults file not honoured on network-manager wireless association

I have edited the /etc/defaults/crda file to configure my system regulatory domain to AU.

When network-manager attaches to the wireless network, this value is not sourced. The regulatory domain switches back to US.
This repeats back and forth, from AU to World to US.

I need some help identifying
- is this a bug?
- am I meant to be using the defaults file for network-manager managed networks?
- if not, where can this be configured correctly?

System detail is:
root@mythtv:/etc/sysctl.d# cat /etc/os-release
NAME="Ubuntu"
VERSION="13.04, Raring Ringtail"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 13.04"
VERSION_ID="13.04"
...

Here is the output from dmesg when this occurs.

[ 15.579701] cfg80211: Calling CRDA for country: AU
[ 15.583170] cfg80211: Regulatory domain changed to country: AU
[ 15.583173] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 15.583174] cfg80211: (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[ 15.583175] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2300 mBm)
[ 15.583176] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2300 mBm)
[ 15.583177] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)
...
[ 22.265820] wlan0: authenticate with 94:44:52:a7:ed:d3
[ 22.313771] wlan0: send auth to 94:44:52:a7:ed:d3 (try 1/3)
[ 22.315735] wlan0: authenticated
[ 22.319045] wlan0: associate with 94:44:52:a7:ed:d3 (try 1/3)
[ 22.320563] wlan0: RX AssocResp from 94:44:52:a7:ed:d3 (capab=0x11 status=0 aid=4)
[ 22.323544] wlan0: associated
[ 22.323571] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 22.323611] cfg80211: Calling CRDA for country: US
[ 22.325924] cfg80211: Regulatory domain changed to country: US
[ 22.325927] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 22.325928] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2700 mBm)
[ 22.325930] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 1700 mBm)
[ 22.325931] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 22.325932] cfg80211: (5490000 KHz - 5600000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 22.325933] cfg80211: (5650000 KHz - 5710000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 22.325934] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)
...
[ 216.856143] wlan0: deauthenticating from 94:44:52:a7:ed:d3 by local choice (reason=3)
[ 216.884265] cfg80211: Calling CRDA to update world regulatory domain
[ 216.890344] cfg80211: World regulatory domain updated:
[ 216.890350] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 216.890355] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 216.890359] cfg80211: (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[ 216.890362] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[ 216.890365] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 216.890368] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 216.890390] cfg80211: Calling CRDA for country: AU
[ 216.895900] cfg80211: Regulatory domain changed to country: AU
[ 216.895904] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 216.895907] cfg80211: (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[ 216.895910] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2300 mBm)
[ 216.895913] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2300 mBm)
[ 216.895915] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)
[ 217.982078] wlan0: authenticate with 94:44:52:a7:ed:d3
[ 218.005788] wlan0: send auth to 94:44:52:a7:ed:d3 (try 1/3)
[ 218.006865] wlan0: authenticated
[ 218.010870] wlan0: associate with 94:44:52:a7:ed:d3 (try 1/3)
[ 218.012486] wlan0: RX AssocResp from 94:44:52:a7:ed:d3 (capab=0x11 status=0 aid=4)
[ 218.015591] wlan0: associated
[ 218.015626] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 218.015680] cfg80211: Calling CRDA for country: US
[ 218.022206] cfg80211: Regulatory domain changed to country: US
[ 218.022210] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 218.022213] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2700 mBm)
[ 218.022216] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 1700 mBm)
[ 218.022218] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 218.022220] cfg80211: (5490000 KHz - 5600000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 218.022222] cfg80211: (5650000 KHz - 5710000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 218.022224] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)
[ 219.332366] IPv6: wlan0: IPv6 duplicate address fe80::16da:e9ff:feb0:6716 detected!
[ 250.982573] wlan0: deauthenticating from 94:44:52:a7:ed:d3 by local choice (reason=3)
[ 251.008487] cfg80211: Calling CRDA to update world regulatory domain
[ 251.014173] cfg80211: World regulatory domain updated:
[ 251.014178] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 251.014181] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 251.014184] cfg80211: (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[ 251.014186] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm)
[ 251.014188] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 251.014192] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 251.014404] cfg80211: Calling CRDA for country: AU
[ 251.019740] cfg80211: Regulatory domain changed to country: AU
[ 251.019744] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 251.019747] cfg80211: (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
[ 251.019750] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2300 mBm)
[ 251.019752] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2300 mBm)
[ 251.019754] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)
[ 252.114384] wlan0: authenticate with 94:44:52:a7:ed:d3
[ 252.138117] wlan0: send auth to 94:44:52:a7:ed:d3 (try 1/3)
[ 252.139172] wlan0: authenticated
[ 252.143055] wlan0: associate with 94:44:52:a7:ed:d3 (try 1/3)
[ 252.144708] wlan0: RX AssocResp from 94:44:52:a7:ed:d3 (capab=0x11 status=0 aid=4)
[ 252.147819] wlan0: associated
[ 252.147847] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[ 252.147895] cfg80211: Calling CRDA for country: US
[ 252.152287] cfg80211: Regulatory domain changed to country: US
[ 252.152291] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
[ 252.152294] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2700 mBm)
[ 252.152297] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 1700 mBm)
[ 252.152299] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 252.152301] cfg80211: (5490000 KHz - 5600000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 252.152303] cfg80211: (5650000 KHz - 5710000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
[ 252.152305] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)

root@mythtv:~# iw reg get
country US:
 (2402 - 2472 @ 40), (3, 27)
 (5170 - 5250 @ 40), (3, 17)
 (5250 - 5330 @ 40), (3, 20), DFS
 (5490 - 5600 @ 40), (3, 20), DFS
 (5650 - 5710 @ 40), (3, 20), DFS
 (5735 - 5835 @ 40), (3, 30)

root@mythtv:/etc# cat default/crda
# Set REGDOMAIN to a ISO/IEC 3166-1 alpha2 country code so that iw(8) may set
# the initial regulatory domain setting for IEEE 802.11 devices which operate
# on this system.
#
# Governments assert the right to regulate usage of radio spectrum within
# their respective territories so make sure you select a ISO/IEC 3166-1 alpha2
# country code suitable for your location or you may infringe on local
# legislature. See `/usr/share/zoneinfo/zone.tab' for a table of timezone
# descriptions containing ISO/IEC 3166-1 alpha2 country codes.

REGDOMAIN=AU