--- a/rqlrewrite.py	Fri Jan 22 14:40:29 2010 +0100
+++ b/rqlrewrite.py	Fri Jan 22 14:41:08 2010 +0100
@@ -327,7 +327,7 @@
             self.compute_solutions()
         except Unsupported:
             # some solutions have been lost, can't apply this rql expr
-            self.select.remove_subquery(new, undefine=True)
+            self.select.remove_subquery(self.select.with_[-1])
             raise
         return subselect