diff -r 49dee01d72f9 Lib/collections.py
--- a/Lib/collections.py	Fri Jun 29 01:42:46 2012 +0200
+++ b/Lib/collections.py	Thu Sep 06 01:24:52 2012 +0200
@@ -275,6 +275,9 @@
         'Return self as a plain tuple.  Used by copy and pickle.'
         return tuple(self)
 
+    def __getstate__(self):
+        return None
+
 {field_defs}
 '''
 
diff -r 49dee01d72f9 Lib/test/test_collections.py
--- a/Lib/test/test_collections.py	Fri Jun 29 01:42:46 2012 +0200
+++ b/Lib/test/test_collections.py	Thu Sep 06 01:24:52 2012 +0200
@@ -169,6 +169,7 @@
                 q = loads(dumps(p, protocol))
                 self.assertEqual(p, q)
                 self.assertEqual(p._fields, q._fields)
+                self.assertNotIn('z', dumps(p, protocol))
 
     def test_copy(self):
         p = TestNT(x=10, y=20, z=30)
@@ -191,6 +192,7 @@
             T = namedtuple('T', 'x', verbose=True)
         words = set(re.findall('[A-Za-z]+', template.getvalue()))
         words -= set(keyword.kwlist)
+        words.remove('None')
         T = namedtuple('T', words)
         # test __new__
         values = tuple(range(len(words)))