Update nose fix to avoid a python 2.6 deprecation warning on exc.message

IPython/testing/plugin/ipdoctest.py

@@ -460,7 +460,7 b' class DocTestCase(doctests.DocTestCase):'
         try:
             super(DocTestCase, self).tearDown()
         except AttributeError, exc:
-            if exc.message != self._result_var:
+            if exc.args[0] != self._result_var:
                 raise