diff --git a/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Authtoken.cs b/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Authtoken.cs
index 3feefa21..1f23695c 100644
--- a/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Authtoken.cs
+++ b/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Authtoken.cs
@@ -36,15 +36,39 @@ namespace Novell.Casa.Client.Auth
 		private const string AUTH_LIBRARY = "C:\\Program Files\\Novell\\CASA\\lib\\authtoken";
 		private const int BUFFER_OVERFLOW = 6;
 
-		[DllImport(AUTH_LIBRARY, CharSet=CharSet.None) ]
-		public static extern int ObtainAuthToken
-			(
-				[In]		byte[] 			baService,		
-				[In]		byte[]  		baHost,
-				[In, Out]	byte[]	 		baToken,							
-				[In, Out]	ref int 		iTokenLength
-			);
+		[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
+		public struct LUID
+		{	
+			public int luidLow;
+			public int luidHigh;
+		}
 
+		[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
+		public class SSCS_EXT_T
+		{
+			public int			extID = 0; 		// defined to identify the extension 
+			public int			version = 0;	// defined as the version of the specified extension
+			public IntPtr		ext;			// points to the actual extension
+		} ;
+
+		[DllImport(AUTH_LIBRARY, CharSet=CharSet.None) ]
+		private static extern int ObtainAuthToken
+		(
+			[In]		byte[] 			baService,		
+			[In]		byte[]  		baHost,
+			[In, Out]	byte[]	 		baToken,							
+			[In, Out]	ref int 		iTokenLength
+		);
+
+		[DllImport(AUTH_LIBRARY, CharSet=CharSet.None) ]
+		private static extern int ObtainAuthTokenEx
+		(
+			[In]		byte[] 			baService,		
+			[In]		byte[]  		baHost,
+			[In, Out]	byte[]	 		baToken,							
+			[In, Out]	ref int 		iTokenLength,
+			[In]		SSCS_EXT_T		ext
+		);
 
 
 		public Authtoken()
@@ -53,11 +77,17 @@ namespace Novell.Casa.Client.Auth
 
 
 		public static byte[] ObtainAuthToken(string sService, string sHost)
+		{
+			return ObtainAuthToken(sService, sHost, null);
+		}
+
+		public static byte[] ObtainAuthToken(string sService, string sHost, WinLuid luid)
 		{
 			int rcode = 0;
 			byte[] baService = null;
 			byte[] baHost =  null;			
 			int bufferSize = 0;			
+			bool bLuidPassedIn = false;
 
 			byte[] baToken = new byte[bufferSize];
 
@@ -81,11 +111,35 @@ namespace Novell.Casa.Client.Auth
 				throw new Exception("Invalid parameter");
 			}
 			
+
+			SSCS_EXT_T ext = new SSCS_EXT_T();
+			if ((luid.GetHighPart() != 0) || (luid.GetLowPart() != 0))
+			{
+				// allocate a structure to marshal
+				LUID sluid = new LUID();
+				sluid.luidHigh = luid.GetHighPart();
+				sluid.luidLow = luid.GetLowPart();
+				
+				ext.extID = 1;
+				ext.version = 1;
+				ext.ext = Marshal.AllocHGlobal(Marshal.SizeOf(sluid));
+
+				Marshal.StructureToPtr(sluid, ext.ext, false);
+				bLuidPassedIn = true;
+			}
+
 			
 			// call with buffersize of 0.  This way we determine the exact size.
 			try
 			{
-				rcode = ObtainAuthToken(baService, baHost, baToken, ref bufferSize);
+				if (bLuidPassedIn)
+				{	
+					rcode = ObtainAuthTokenEx(baService, baHost, baToken, ref bufferSize, ext);
+				}
+				else
+				{
+					rcode = ObtainAuthToken(baService, baHost, baToken, ref bufferSize);
+				}
 				
 				int test = (rcode & BUFFER_OVERFLOW);
 				if (test == BUFFER_OVERFLOW)
@@ -101,6 +155,8 @@ namespace Novell.Casa.Client.Auth
 				return null;
 			}
 									
+			if (ext.ext != IntPtr.Zero)
+				Marshal.FreeHGlobal(ext.ext);
 
 			if (rcode != 0)
 			{				
diff --git a/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Novell.Casa.Client.csproj b/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Novell.Casa.Client.csproj
index 1f419bbd..89da51ec 100644
--- a/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Novell.Casa.Client.csproj
+++ b/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/Novell.Casa.Client.csproj
@@ -93,6 +93,11 @@
                     SubType = "Code"
                     BuildAction = "Compile"
                 />
+                <File
+                    RelPath = "WinLuid.cs"
+                    SubType = "Code"
+                    BuildAction = "Compile"
+                />
             </Include>
         </Files>
     </CSHARP>
diff --git a/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/WinLuid.cs b/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/WinLuid.cs
new file mode 100644
index 00000000..bb7e753d
--- /dev/null
+++ b/CASA-auth-token/non-java/client/csharp/Novell.Casa.Authtoken/WinLuid.cs
@@ -0,0 +1,29 @@
+using System;
+
+namespace Novell.Casa.Client.Auth
+{
+	/// <summary>
+	/// Summary description for WinLuid.
+	/// </summary>
+	public class WinLuid
+	{
+		private int m_low = 0;
+		private int m_high = 0;
+
+		public WinLuid(int lowPart, int highPart )
+		{
+			m_low = lowPart;
+			m_high = highPart;
+		}
+
+		public int GetLowPart()
+		{
+			return m_low;
+		}
+
+		public int GetHighPart()
+		{
+			return m_high;
+		}
+	}
+}
diff --git a/CASA-auth-token/non-java/client/csharp/test/Class1.cs b/CASA-auth-token/non-java/client/csharp/test/Class1.cs
index 87aa14aa..313e455b 100644
--- a/CASA-auth-token/non-java/client/csharp/test/Class1.cs
+++ b/CASA-auth-token/non-java/client/csharp/test/Class1.cs
@@ -48,6 +48,10 @@ namespace TestClientAuth
 
 			try
 			{
+
+				WinLuid luid = new WinLuid(1234, 5678);
+				Authtoken.ObtainAuthToken("testService", args[0], luid);
+
 				byte[] baToken = Authtoken.ObtainAuthToken("testService", args[0]);
 				Console.WriteLine("Token returned: ("+ baToken.Length + ")");
 				for (int i=0; i<baToken.Length; i++)