--- a/Interval.st	Wed Jun 24 15:30:08 2015 +0200
+++ b/Interval.st	Thu Jun 25 18:31:31 2015 +0200
@@ -1,3 +1,5 @@
+"{ Encoding: utf8 }"
+
 "
  COPYRIGHT (c) 1989 by Claus Gittinger
               All Rights Reserved
@@ -11,6 +13,8 @@
 "
 "{ Package: 'stx:libbasic' }"
 
+"{ NameSpace: Smalltalk }"
+
 ReadOnlySequenceableCollection subclass:#Interval
 	instanceVariableNames:'start stop step'
 	classVariableNames:''
@@ -535,12 +539,12 @@
         (start < stop) ifTrue:[
             ^ 0
         ].
-        ^ stop - start // step + 1
+        ^ (start - stop) // step abs + 1
     ].
     (stop < start) ifTrue:[
         ^ 0
     ].
-    ^ stop - start // step + 1
+    ^ (stop - start) // step + 1
 ! !
 
 !Interval methodsFor:'set operations'!
@@ -690,10 +694,10 @@
 !Interval class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Interval.st,v 1.57 2014-07-10 12:23:57 cg Exp $'
+    ^ '$Header$'
 !
 
 version_CVS
-    ^ '$Header: /cvs/stx/stx/libbasic/Interval.st,v 1.57 2014-07-10 12:23:57 cg Exp $'
+    ^ '$Header$'
 ! !