Index: pdb.py
===================================================================
--- pdb.py	(revision 80143)
+++ pdb.py	(working copy)
@@ -61,7 +61,7 @@
     def __init__(self, completekey='tab', stdin=None, stdout=None, skip=None):
         bdb.Bdb.__init__(self, skip=skip)
         cmd.Cmd.__init__(self, completekey, stdin, stdout)
-        if stdout:
+        if stdout and stdout != sys.stdout:
             self.use_rawinput = 0
         self.prompt = '(Pdb) '
         self.aliases = {}
Index: doctest.py
===================================================================
--- doctest.py	(revision 80143)
+++ doctest.py	(working copy)
@@ -1361,7 +1361,6 @@
         save_stdout = sys.stdout
         if out is None:
             out = save_stdout.write
-        sys.stdout = self._fakeout
 
         # Patch pdb.set_trace to restore sys.stdout during interactive
         # debugging (so it's not still redirected to self._fakeout).
@@ -1373,6 +1372,8 @@
         self.debugger.reset()
         pdb.set_trace = self.debugger.set_trace
 
+        sys.stdout = self._fakeout
+
         # Patch linecache.getlines, so we can see the example's source
         # when we're inside the debugger.
         self.save_linecache_getlines = linecache.getlines
Index: test/test_doctest.py
===================================================================
--- test/test_doctest.py	(revision 80537)
+++ test/test_doctest.py	(working copy)
@@ -1583,6 +1583,17 @@
 
 """
 
+def test_pdb_readline_use ():
+    """
+    When using pdb in doctest's test cases, the readline library 
+    must be used to retrieve pdb commands from history
+
+    Readline method is enabled when Cmd's use_rawinput varaible is 1.
+
+      >>> doctest_pdb = doctest._OutputRedirectingPdb (sys.stdout)
+      >>> assert doctest_pdb.use_rawinput == 1, 'Readline not used'
+    """
+
 def test_pdb_set_trace():
     """Using pdb.set_trace from a doctest.
 
@@ -1592,7 +1603,7 @@
     capture program output.  It also temporarily replaces pdb.set_trace
     with a version that restores stdout.  This is necessary for you to
     see debugger output.
-
+        
       >>> doc = '''
       ... >>> x = 42
       ... >>> import pdb; pdb.set_trace()