Index: elixir/trunk/elixir/ext/list.py
===================================================================
--- elixir/trunk/elixir/ext/list.py (revision 293)
+++ elixir/trunk/elixir/ext/list.py (revision 309)
@@ -123,5 +123,6 @@
                 select([literal(1).label('value')])
             )
-            setattr(self, position_column_name, select([func.max(s.c.value)]))
+            a = s.alias()
+            setattr(self, position_column_name, select([func.max(a.c.value)]))
         
         @before_delete