diff -r ef80ce83eab1 Doc/library/threading.rst
--- a/Doc/library/threading.rst	Fri Aug 31 13:55:11 2012 +0300
+++ b/Doc/library/threading.rst	Fri Aug 31 05:09:07 2012 -0700
@@ -184,6 +184,11 @@
    the suggested approach in the absence of more specific information).
    Availability: Windows, systems with POSIX threads.
 
+This module also defines the following exception:
+
+.. exception:: ThreadError
+
+    Raised when lock object cannot be acquired or released.
 
 This module also defines the following constant:
 
@@ -409,7 +414,7 @@
 to locked and returns.  The :meth:`~Lock.release` method should only be
 called in the locked state; it changes the state to unlocked and returns
 immediately. If an attempt is made to release an unlocked lock, a
-:exc:`RuntimeError` will be raised.
+:exc:`ThreadError` will be raised.
 
 Locks also support the :ref:`context manager protocol <with-locks>`.