diff --git a/ChangeLog b/ChangeLog
index eba01002c..d788bcd73 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2004-08-21  Fred Kiefer <FredKiefer@gmx.de>
+
+	* Source/NSComboBoxCell.m (-completedString:):  Handle a nil
+	substring by returning nil directly without trying to find a
+	match. Patch by Andreas Hoeschler <ahoesch@smartsoft.de>.
+	Changed data source error messages to consistent wording.
+	
 2004-08-13  Quentin Mathe <qmathe@club-internet.fr>
         
 	* Source/NSComboBoxCell.m:
diff --git a/Source/NSComboBoxCell.m b/Source/NSComboBoxCell.m
index 3ba9d4e89..ce4809538 100644
--- a/Source/NSComboBoxCell.m
+++ b/Source/NSComboBoxCell.m
@@ -980,7 +980,7 @@ numberOfRowsInColumn: (int)column
     {
       if (!_dataSource)
         {
-	  NSLog(@"%@: A DataSource should be specified", self);
+	  NSLog(@"%@: No data source currently specified", self);
 	}
       else
         {
@@ -1287,10 +1287,17 @@ numberOfRowsInColumn: (int)column
  */
 - (NSString *)completedString:(NSString *)substring
 {
+  if (nil == substring)
+    {
+      return nil;
+    }
+
   if (_usesDataSource)
     {
       if (!_dataSource)
-	NSLog(@"%@: A data source should be specified", self);
+        {
+	  NSLog(@"%@: No data source currently specified", self);
+	}
       else if ([_dataSource respondsToSelector: @selector(comboBox:completedString:)])
         {
 	  return [_dataSource comboBox: (NSComboBox *)[self controlView] 
@@ -1837,7 +1844,7 @@ static inline NSRect buttonCellFrameFromRect(NSRect cellRect)
     {
       if (!_dataSource)
         {
-	  NSLog(@"%@: A DataSource should be specified", self);
+	  NSLog(@"%@: No data source currently specified", self);
 	}
       else
         {