diff --git a/NEWS.rst b/NEWS.rst
index f25f0a6..fd3cde5 100644
--- a/NEWS.rst
+++ b/NEWS.rst
@@ -5,6 +5,8 @@ Release History
 0.3 (2012-01-XX)
 ~~~~~~~~~~~~~~~~
 
+* Issue #5: ContextStack.register no longer pointlessly returns the wrapped
+  function
 * Issue #2: Add examples and recipes section to docs
 * Issue #3: ContextStack.register_exit() now accepts objects with __exit__
   attributes in addition to accepting exit callbacks directly
diff --git a/contextlib2.py b/contextlib2.py
index 2b95040..a9c24a3 100644
--- a/contextlib2.py
+++ b/contextlib2.py
@@ -187,7 +187,7 @@ class ContextStack(object):
         @wraps(callback)
         def _wrapper(exc_type, exc, tb):
             callback(*args, **kwds)
-        return self.register_exit(_wrapper)
+        self.register_exit(_wrapper)
 
     def enter_context(self, cm):
         """Enters the supplied context manager
diff --git a/test_contextlib2.py b/test_contextlib2.py
index 31b95b0..8ee7bdb 100755
--- a/test_contextlib2.py
+++ b/test_contextlib2.py
@@ -322,13 +322,13 @@ class TestContextStack(unittest.TestCase):
         with ContextStack() as stack:
             for args, kwds in reversed(expected):
                 if args and kwds:
-                    stack.register(_exit, *args, **kwds)
+                    self.assertIsNone(stack.register(_exit, *args, **kwds))
                 elif args:
-                    stack.register(_exit, *args)
+                    self.assertIsNone(stack.register(_exit, *args))
                 elif kwds:
-                    stack.register(_exit, **kwds)
+                    self.assertIsNone(stack.register(_exit, **kwds))
                 else:
-                    stack.register(_exit)
+                    self.assertIsNone(stack.register(_exit))
             for wrapper in stack._callbacks:
                 self.assertEqual(wrapper.__name__, _exit.__name__)
                 self.assertEqual(wrapper.__doc__, _exit.__doc__)