Index: includes/database/select.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/database/select.inc,v
retrieving revision 1.56
diff -u -p -r1.56 select.inc
--- includes/database/select.inc	22 Dec 2010 08:13:58 -0000	1.56
+++ includes/database/select.inc	22 Dec 2010 22:38:28 -0000
@@ -1362,7 +1362,7 @@ class SelectQuery extends Query implemen
     // Create our new query object that we will mutate into a count query.
     $count = clone($this);
 
-    $group_by = array_keys($count->getGroupBy());
+    $group_by = drupal_map_assoc(array_values($count->getGroupBy()));
 
     if (!$count->distinct) {
       // When not executing a distinct query, we can zero-out existing fields