diff --git a/ChangeLog b/ChangeLog
index ebc3d8cf5..1998ecdc1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2004-10-31 Richard Frith-Macdonald <rfm@gnu.org>
+
+	* Source/NSUserDefaults.m: ([setObject:forKey:]) when given a nil
+	value to set, remove any existing object for the key.  Fix for
+	MacOS-X compatibility (bug #10743).
+
 2004-10-29  Matt Rice  <ratmice@yahoo.com>
 
 	* Source/Additions/GSObjCRuntime.m (GSObjCAllSubclassesOfClass,
diff --git a/Source/NSUserDefaults.m b/Source/NSUserDefaults.m
index 05ad463d9..5eeafcba7 100644
--- a/Source/NSUserDefaults.m
+++ b/Source/NSUserDefaults.m
@@ -1194,23 +1194,23 @@ static BOOL isPlistObject(id o)
  * if this is the first change to a persistent-domain since the
  * last -synchronize.
  * </p>
+ * If value is nil, this is equivalent to the -removeObjectForKey: method.
  */
 - (void) setObject: (id)value forKey: (NSString*)defaultName
 {
   NSMutableDictionary	*dict;
   id			obj;
 
+  if (value == nil)
+    {
+      [self removeObjectForKey: defaultName];
+    }
   if ([defaultName isKindOfClass: [NSString class]] == NO
     || [defaultName length] == 0)
     {
       [NSException raise: NSInvalidArgumentException
 	format: @"attempt to set object with bad key (%@)", defaultName];
     }
-  if (value == nil)
-    {
-      [NSException raise: NSInvalidArgumentException
-	format: @"attempt to set nil object for key (%@)", defaultName];
-    }
   if (isPlistObject(value) == NO)
     {
       [NSException raise: NSInvalidArgumentException