diff -r de287a94b486 Lib/unittest/mock.py
--- a/Lib/unittest/mock.py	Tue Aug 05 14:01:10 2014 -0500
+++ b/Lib/unittest/mock.py	Wed Aug 06 03:46:24 2014 -0500
@@ -1308,7 +1308,10 @@
             setattr(self.target, self.attribute, self.temp_original)
         else:
             delattr(self.target, self.attribute)
-            if not self.create and not hasattr(self.target, self.attribute):
+            if not self.create and (not hasattr(self.target,
+                                                self.attribute) or
+                self.attribute in ('__doc__', '__module__', '__defaults__',
+                                   '__annotations__', '__kwdefaults__')):
                 # needed for proxy objects like django settings
                 setattr(self.target, self.attribute, self.temp_original)
 
diff -r de287a94b486 Lib/unittest/test/testmock/testpatch.py
--- a/Lib/unittest/test/testmock/testpatch.py	Tue Aug 05 14:01:10 2014 -0500
+++ b/Lib/unittest/test/testmock/testpatch.py	Wed Aug 06 03:46:24 2014 -0500
@@ -1797,5 +1797,31 @@
         self.assertEqual(stopped, ["three", "two", "one"])
 
 
+    def test_special_attrs(self):
+        def foo(x=0):
+            """TEST"""
+            return x
+        with patch.object(foo, '__defaults__', (1, )):
+            self.assertEqual(foo(), 1)
+        self.assertEqual(foo(), 0)
+
+        with patch.object(foo, '__doc__', "FUN"):
+            self.assertEqual(foo.__doc__, "FUN")
+        self.assertEqual(foo.__doc__, "TEST")
+
+        with patch.object(foo, '__module__', "testpatch2"):
+            self.assertEqual(foo.__module__, "testpatch2")
+        self.assertEqual(foo.__module__, 'unittest.test.testmock.testpatch')
+
+        with patch.object(foo, '__annotations__', dict([('s', 1, )])):
+            self.assertEqual(foo.__annotations__, dict([('s', 1, )]))
+        self.assertEqual(foo.__annotations__, dict())
+
+        def foo(*a, x=0):
+            return x
+        with patch.object(foo, '__kwdefaults__', dict([('x', 1, )])):
+            self.assertEqual(foo(), 1)
+        self.assertEqual(foo(), 0)
+
 if __name__ == '__main__':
     unittest.main()