--- a/devtools/testlib.py	Wed Aug 25 09:43:12 2010 +0200
+++ b/devtools/testlib.py	Wed Aug 25 10:01:11 2010 +0200
@@ -903,7 +903,8 @@
         for action in self.list_actions_for(rset):
             yield InnerTest(self._testname(rset, action.__regid__, 'action'), self._test_action, action)
         for box in self.list_boxes_for(rset):
-            yield InnerTest(self._testname(rset, box.__regid__, 'box'), box.render)
+            w = [].append
+            yield InnerTest(self._testname(rset, box.__regid__, 'box'), box.render, w)
 
     @staticmethod
     def _testname(rset, objid, objtype):