--- a/server/test/unittest_msplanner.py	Thu Feb 14 15:38:25 2013 +0100
+++ b/server/test/unittest_msplanner.py	Thu Feb 14 16:01:24 2013 +0100
@@ -149,7 +149,7 @@
         plan.preprocess(union)
         ppi = PartPlanInformation(plan, union.children[0])
         for sourcevars in ppi._sourcesterms.itervalues():
-            for var in sourcevars.keys():
+            for var in list(sourcevars):
                 solindices = sourcevars.pop(var)
                 sourcevars[var._ms_table_key()] = solindices
         self.assertEqual(ppi._sourcesterms, sourcesterms)