diff --git a/ChangeLog b/ChangeLog
index 094ef8cb5..e1aa673ae 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2005-03-31  Mike Kestner  <mkestner@novell.com>
+
+	* glib/ManagedValue.cs : add null/NULL guarding to Copy, Free, 
+	WrapObject, and ObjectForWrapper.  [Fixes #74197]
+
 2005-03-30  Jeroen Zwartepoorte  <jeroen@xs4all.nl>
 
 	* parser/gapi2xml.pl : parse gst type macros.
diff --git a/glib/ManagedValue.cs b/glib/ManagedValue.cs
index 1f5d2d98a..5923524d6 100644
--- a/glib/ManagedValue.cs
+++ b/glib/ManagedValue.cs
@@ -56,23 +56,31 @@ namespace GLib {
 		
 		static IntPtr Copy (IntPtr ptr)
 		{
+			if (ptr == IntPtr.Zero)
+				return ptr;
 			GCHandle gch = (GCHandle) ptr;
 			return (IntPtr) GCHandle.Alloc (gch.Target);
 		}
 
 		static void Free (IntPtr ptr)
 		{
+			if (ptr == IntPtr.Zero)
+				return;
 			GCHandle gch = (GCHandle) ptr;
 			gch.Free ();
 		}
 
 		public static IntPtr WrapObject (object obj)
 		{
+			if (obj == null)
+				return IntPtr.Zero;
 			return (IntPtr) GCHandle.Alloc (obj);
 		}
 
 		public static object ObjectForWrapper (IntPtr ptr)
 		{
+			if (ptr == IntPtr.Zero)
+				return null;
 			return ((GCHandle)ptr).Target;
 		}
 	}
diff --git a/sample/ManagedTreeViewDemo.cs b/sample/ManagedTreeViewDemo.cs
index cd53b4036..ef06e4061 100644
--- a/sample/ManagedTreeViewDemo.cs
+++ b/sample/ManagedTreeViewDemo.cs
@@ -24,7 +24,7 @@ namespace GtkSamples {
 		private static void PopulateStore ()
 		{
 			store = new ListStore (typeof (Pair));
-			string[] combs = {"foo", "bar", "baz", "quux"};
+			string[] combs = {null, "foo", "bar", "baz"};
 			foreach (string a in combs) {
 				foreach (string b in combs) {
 					store.AppendValues (new Pair (a, b));