diff --git a/IPython/kernel/zmq/tests/test_session.py b/IPython/kernel/zmq/tests/test_session.py
index 06b6d6f..36c8d40 100644
--- a/IPython/kernel/zmq/tests/test_session.py
+++ b/IPython/kernel/zmq/tests/test_session.py
@@ -13,6 +13,8 @@
 
 import os
 import uuid
+from datetime import datetime
+
 import zmq
 
 from zmq.tests import BaseZMQTestCase
@@ -20,6 +22,10 @@ from zmq.eventloop.zmqstream import ZMQStream
 
 from IPython.kernel.zmq import session as ss
 
+from IPython.testing.decorators import skipif, module_not_available
+from IPython.utils.py3compat import string_types
+from IPython.utils import jsonutil
+
 def _bad_packer(obj):
     raise TypeError("I don't work")
 
@@ -155,24 +161,6 @@ class TestSession(SessionTestCase):
         t.wait(1) # this will raise
 
 
-    # def test_rekey(self):
-    #     """rekeying dict around json str keys"""
-    #     d = {'0': uuid.uuid4(), 0:uuid.uuid4()}
-    #     self.assertRaises(KeyError, ss.rekey, d)
-    #
-    #     d = {'0': uuid.uuid4(), 1:uuid.uuid4(), 'asdf':uuid.uuid4()}
-    #     d2 = {0:d['0'],1:d[1],'asdf':d['asdf']}
-    #     rd = ss.rekey(d)
-    #     self.assertEqual(d2,rd)
-    #
-    #     d = {'1.5':uuid.uuid4(),'1':uuid.uuid4()}
-    #     d2 = {1.5:d['1.5'],1:d['1']}
-    #     rd = ss.rekey(d)
-    #     self.assertEqual(d2,rd)
-    #
-    #     d = {'1.0':uuid.uuid4(),'1':uuid.uuid4()}
-    #     self.assertRaises(KeyError, ss.rekey, d)
-    #
     def test_unique_msg_ids(self):
         """test that messages receive unique ids"""
         ids = set()
@@ -267,5 +255,35 @@ class TestSession(SessionTestCase):
     
     def test_bad_roundtrip(self):
         with self.assertRaises(ValueError):
-            session=  ss.Session(unpack=lambda b: 5)
+            session = ss.Session(unpack=lambda b: 5)
+    
+    def _datetime_test(self, session):
+        content = dict(t=datetime.now())
+        metadata = dict(t=datetime.now())
+        p = session.msg('msg')
+        msg = session.msg('msg', content=content, metadata=metadata, parent=p['header'])
+        smsg = session.serialize(msg)
+        msg2 = session.unserialize(session.feed_identities(smsg)[1])
+        assert isinstance(msg2['header']['date'], datetime)
+        self.assertEqual(msg['header'], msg2['header'])
+        self.assertEqual(msg['parent_header'], msg2['parent_header'])
+        self.assertEqual(msg['parent_header'], msg2['parent_header'])
+        assert isinstance(msg['content']['t'], datetime)
+        assert isinstance(msg['metadata']['t'], datetime)
+        assert isinstance(msg2['content']['t'], string_types)
+        assert isinstance(msg2['metadata']['t'], string_types)
+        self.assertEqual(msg['content'], jsonutil.extract_dates(msg2['content']))
+        self.assertEqual(msg['content'], jsonutil.extract_dates(msg2['content']))
+    
+    def test_datetimes(self):
+        self._datetime_test(self.session)
+    
+    def test_datetimes_pickle(self):
+        session = ss.Session(packer='pickle')
+        self._datetime_test(session)
+    
+    @skipif(module_not_available('msgpack'))
+    def test_datetimes_msgpack(self):
+        session = ss.Session(packer='msgpack.packb', unpacker='msgpack.unpackb')
+        self._datetime_test(session)