diff -r 5406c963ee81 -r 01b23ec9c066 rqlrewrite.py
--- a/rqlrewrite.py	Tue Mar 29 10:25:10 2011 +0200
+++ b/rqlrewrite.py	Wed Mar 30 11:07:07 2011 +0200
@@ -252,7 +252,8 @@
                 self.insert_pending()
                 self._insert_scope = None
                 return
-            new = n.Exists(new)
+            if not isinstance(new, (n.Exists, n.Not)):
+                new = n.Exists(new)
             if parent is None:
                 insert_scope.add_restriction(new)
             else: