os authentication on nt

	Hi,
		Can anyone provide me with the 
	correct way to get OS authentication to 
	work on NT, version 8.1.6.

	I've searched Metalink and found a few notes,
	but I've been unsuccessful with the procedures
	they recommend.

	Using "sqlplus/nolog" , or svrmgrl I can
	successfully do a "connect internal".
	The user name is "oracle" and it has 
	administrator privileges on the local domain.
	Do I need a password file ? I'm currently not using
	one.
	Any help would be appreciated. Thanks.