diff --git a/ChangeLog b/ChangeLog
index 5a2dcd4c7..76e7d014f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2004-03-26 Fred Kiefer <FredKiefer@gmx.de>
+
+	* Source/NSIndexSet.m: Check before each usage of _other if it is
+	actually set.
+
 2004-03-24  Adam Fedor  <fedor@gnu.org>
 
 	* Resources/GNUmakefile: Add Languages/Hungarian.
diff --git a/Source/NSIndexSet.m b/Source/NSIndexSet.m
index 86f26f456..83298f384 100644
--- a/Source/NSIndexSet.m
+++ b/Source/NSIndexSet.m
@@ -460,7 +460,7 @@ static unsigned posForIndex(GSIArray array, unsigned index)
     }
   else
     {
-      unsigned	count = GSIArrayCount(_other);
+      unsigned count = _other ? GSIArrayCount(_other) : 0;
 
       if (count > 0)
 	{
@@ -580,7 +580,7 @@ static unsigned posForIndex(GSIArray array, unsigned index)
 
 - (void) addIndexes: (NSIndexSet*)aSet
 {
-  unsigned	count = GSIArrayCount(_other);
+  unsigned	count = _other ? GSIArrayCount(_other) : 0;
 
   if (count > 0)
     {
@@ -701,7 +701,7 @@ static unsigned posForIndex(GSIArray array, unsigned index)
 
 - (void) removeIndexes: (NSIndexSet*)aSet
 {
-  unsigned	count = GSIArrayCount(_other);
+  unsigned	count = _other ? GSIArrayCount(_other) : 0;
 
   if (count > 0)
     {