Index: Doc/library/unittest.rst
===================================================================
--- Doc/library/unittest.rst	(revision 73271)
+++ Doc/library/unittest.rst	(working copy)
@@ -888,6 +888,9 @@
          with self.failUnlessRaises(some_error_class):
              do_something()
 
+      The context manager will store the caught exception object in its
+      :attr:`exc_value` attribute. 
+
       .. versionchanged:: 2.7
          Added the ability to use :meth:`assertRaises` as a context manager.
 
Index: Lib/test/test_unittest.py
===================================================================
--- Lib/test/test_unittest.py	(revision 73271)
+++ Lib/test/test_unittest.py	(working copy)
@@ -2820,6 +2820,21 @@
                 self.assertRaisesRegexp, Exception,
                 re.compile('^Expected$'), Stub)
 
+    def testAssertRaisesExcValue(self):
+        class ExceptionMock(Exception):
+            pass
+
+        def Stub(foo):
+            raise ExceptionMock(foo)
+        v = "particular value"
+
+        ctx = self.assertRaises(ExceptionMock)
+        with ctx:
+            Stub(v)
+        e = ctx.exc_value
+        self.assertTrue(isinstance(e, ExceptionMock))
+        self.assertEqual(e.args[0], v)
+
     def testSynonymAssertMethodNames(self):
         """Test undocumented method name synonyms.
 
Index: Lib/unittest.py
===================================================================
--- Lib/unittest.py	(revision 73271)
+++ Lib/unittest.py	(working copy)
@@ -291,6 +291,9 @@
         if not issubclass(exc_type, self.expected):
             # let unexpected exceptions pass through
             return False
+
+        self.exc_value = exc_value #store for later retrieval
+
         if self.expected_regex is None:
             return True