country code of wireless LAN adapter

here i am using deviceIOControl to get the country code of wireless LAN
adapter

code is as follows:

NDIS_OID ndisOid
//Atheros Specific OID
ndisOid = OID_ATH_REGULATORY_DOMAIN;

DeviceIoControl(theApp.m_hDevHandle,
IOCTL_NDIS_QUERY_GLOBAL_STATS,
(LPVOID)&ndisOid,
sizeof(ndisOid) + sizeof (ULONG) -1,
(LPVOID)&dwCountryCode,
sizeof(dwCountryCode),
&ulLen,
NULL);

this is working for WindowsXp, but not for Windows Vista.
can any body help me in this?????

to resolve this problem i got the information from MSDN site that it
need to use WMI through the class "MSNdis_80211_WEPStatus".
i have seen it through WMI browser. but not getting any relevent
information