--- a/thirdparty/google_appengine/google/appengine/datastore/datastore_index.py	Tue Jan 20 01:12:43 2009 +0000
+++ b/thirdparty/google_appengine/google/appengine/datastore/datastore_index.py	Tue Jan 20 13:19:45 2009 +0000
@@ -332,6 +332,11 @@
       (not props or (len(props) == 1 and props[0][1] == ASCENDING))):
     required = False
 
+    if props:
+      prop, dir = props[0]
+      if prop in datastore_types._SPECIAL_PROPERTIES and dir is DESCENDING:
+        required = True
+
   unique_names = set(name for name, dir in props)
   if len(props) > 1 and len(unique_names) == 1:
     required = False