--- a/ChangeSetBrowser.st	Tue Jun 06 06:21:18 1995 +0200
+++ b/ChangeSetBrowser.st	Tue Jun 27 04:30:28 1995 +0200
@@ -21,7 +21,7 @@
 COPYRIGHT (c) 1993 by Claus Gittinger
 	      All Rights Reserved
 
-$Header: /cvs/stx/stx/libtool/ChangeSetBrowser.st,v 1.4 1994-11-17 14:47:59 claus Exp $
+$Header: /cvs/stx/stx/libtool/ChangeSetBrowser.st,v 1.5 1995-06-27 02:29:17 claus Exp $
 '!
 
 !ChangeSetBrowser class methodsFor:'documentation'!
@@ -42,7 +42,7 @@
 
 version
 "
-$Header: /cvs/stx/stx/libtool/ChangeSetBrowser.st,v 1.4 1994-11-17 14:47:59 claus Exp $
+$Header: /cvs/stx/stx/libtool/ChangeSetBrowser.st,v 1.5 1995-06-27 02:29:17 claus Exp $
 "
 !
 
@@ -128,8 +128,10 @@
 changeSet:aChangeSet
     originalChangeSet := aChangeSet.
     changeSet := OrderedCollection new.
-    originalChangeSet do:[:aChange |
-	changeSet add:aChange
+    originalChangeSet notNil ifTrue:[
+	originalChangeSet do:[:aChange |
+	    changeSet add:aChange
+	].
     ].
 !