Document need to call doctest_reload() with older Python versions

IPython/utils/doctestreload.py

@@ -52,13 +52,13 b' def doctest_reload():'
       - imports doctest but does NOT reload it (see below).
 
       - resets its global 'master' attribute to None, so that multiple uses of
-      the module interactively don't produce cumulative reports.
+        the module interactively don't produce cumulative reports.
 
       - Monkeypatches its core test runner method to protect it from IPython's
-      modified displayhook.  Doctest expects the default displayhook behavior
-      deep down, so our modification breaks it completely.  For this reason, a
-      hard monkeypatch seems like a reasonable solution rather than asking
-      users to manually use a different doctest runner when under IPython.
+        modified displayhook.  Doctest expects the default displayhook behavior
+        deep down, so our modification breaks it completely.  For this reason, a
+        hard monkeypatch seems like a reasonable solution rather than asking
+        users to manually use a different doctest runner when under IPython.
 
     Notes
     -----

docs/source/whatsnew/development.txt

@@ -40,3 +40,7 b' Backwards incompatible changes'
   :mod:`IPython.lib.inputhook`.
 * For all kernel managers, the ``sub_channel`` attribute has been renamed to
   ``iopub_channel``.
+* Users on Python versions before 2.6.6, 2.7.1 or 3.2 will now need to call
+  :func:`IPython.utils.doctestreload.doctest_reload` to make doctests run 
+  correctly inside IPython. Python releases since those versions are unaffected.
+  For details, see :ghpull:`3068` and `Python issue 8048 <http://bugs.python.org/issue8048>`_.