Index: Lib/doctest.py
===================================================================
--- Lib/doctest.py	(revision 78630)
+++ Lib/doctest.py	(working copy)
@@ -1377,12 +1377,17 @@
         self.save_linecache_getlines = linecache.getlines
         linecache.getlines = self.__patched_linecache_getlines
 
+        # Make sure sys.displayhook just prints the value to stdout
+        save_displayhook = sys.displayhook
+        sys.displayhook = sys.__displayhook__
+        
         try:
             return self.__run(test, compileflags, out)
         finally:
             sys.stdout = save_stdout
             pdb.set_trace = save_set_trace
             linecache.getlines = self.save_linecache_getlines
+            sys.displayhook = save_displayhook
             if clear_globs:
                 test.globs.clear()
 
Index: Lib/test/test_doctest.py
===================================================================
--- Lib/test/test_doctest.py	(revision 78630)
+++ Lib/test/test_doctest.py	(working copy)
@@ -910,6 +910,35 @@
         ZeroDivisionError: integer division or modulo by zero
     TestResults(failed=1, attempted=1)
 """
+    def displayhook(): r"""
+Test that changing sys.displayhook doesn't matter for doctest.
+
+    >>> import sys
+    >>> orig_displayhook = sys.displayhook
+    >>> def my_displayhook(x):
+    ...     print 'hi!'
+    >>> sys.displayhook = my_displayhook
+    >>> def f():
+    ...     '''
+    ...     >>> 3
+    ...     3
+    ...     '''
+    >>> test = doctest.DocTestFinder().find(f)[0]
+    >>> r = doctest.DocTestRunner(verbose=False).run(test)
+    >>> post_displayhook = sys.displayhook
+    
+    We need to restore sys.displayhook now, so that we'll be able to test
+    results.
+    
+    >>> sys.displayhook = orig_displayhook
+    
+    Ok, now we can check that everything is ok.
+    
+    >>> r
+    TestResults(failed=0, attempted=1)
+    >>> post_displayhook is my_displayhook
+    True
+"""
     def optionflags(): r"""
 Tests of `DocTestRunner`'s option flag handling.