diff -r 6f2de09b29e8 -r addb81a42c5d cwconfig.py
--- a/cwconfig.py	Fri Mar 02 09:44:58 2012 +0100
+++ b/cwconfig.py	Thu Mar 01 17:22:56 2012 +0100
@@ -825,7 +825,7 @@
     _cubes = None
 
     def init_cubes(self, cubes):
-        assert self._cubes is None, self._cubes
+        assert self._cubes is None, repr(self._cubes)
         self._cubes = self.reorder_cubes(cubes)
         # load cubes'__init__.py file first
         for cube in cubes: