--- a/genshi/core.py
+++ b/genshi/core.py
@@ -22,6 +22,11 @@
 
 class StreamEventKind(str):
     """A kind of event on an XML stream."""
+    __slots__ = []
+    _instances = {}
+
+    def __new__(cls, val):
+        return cls._instances.setdefault(val, str.__new__(cls, val))
 
 
 class Stream(object):
@@ -503,6 +508,15 @@
             return uri
         return object.__new__(cls, uri)
 
+    def __getnewargs__(self):
+        return (self.uri,)
+
+    def __getstate__(self):
+        return self.uri
+
+    def __setstate__(self, uri):
+        self.uri = uri
+
     def __init__(self, uri):
         self.uri = unicode(uri)
 
@@ -572,3 +586,6 @@
             self = unicode.__new__(cls, qname)
             self.namespace, self.localname = None, unicode(qname)
         return self
+
+    def __getnewargs__(self):
+        return (self.lstrip('{'),)

--- a/genshi/tests/core.py
+++ b/genshi/tests/core.py
@@ -12,9 +12,12 @@
 # history and logs, available at http://genshi.edgewall.org/log/.
 
 import doctest
+import pickle
+from StringIO import StringIO
 import unittest
 
-from genshi.core import *
+from genshi import core
+from genshi.core import Markup, Namespace, QName, escape, unescape
 from genshi.input import XML, ParseError
 
 
@@ -32,6 +35,14 @@
         xml = XML('<li>Über uns</li>')
         self.assertEqual('<li>&#220;ber uns</li>', xml.render(encoding='ascii'))
 
+    def test_pickle(self):
+        xml = XML('<li>Foo</li>')
+        buf = StringIO()
+        pickle.dump(xml, buf, 2)
+        buf.seek(0)
+        xml = pickle.load(buf)
+        self.assertEquals('<li>Foo</li>', xml.render())
+
 
 class MarkupTestCase(unittest.TestCase):
 
@@ -115,12 +126,48 @@
         assert type(markup) is Markup
         self.assertEquals('foo', markup)
 
+    def test_pickle(self):
+        markup = Markup('foo')
+        buf = StringIO()
+        pickle.dump(markup, buf, 2)
+        buf.seek(0)
+        self.assertEquals('<Markup "foo">', repr(pickle.load(buf)))
+
+
+class NamespaceTestCase(unittest.TestCase):
+
+    def test_pickle(self):
+        ns = Namespace('http://www.example.org/namespace')
+        buf = StringIO()
+        pickle.dump(ns, buf, 2)
+        buf.seek(0)
+        unpickled = pickle.load(buf)
+        self.assertEquals('<Namespace "http://www.example.org/namespace">',
+                          repr(unpickled))
+        self.assertEquals('http://www.example.org/namespace', unpickled.uri)
+
+
+class QNameTestCase(unittest.TestCase):
+
+    def test_pickle(self):
+        qname = QName('http://www.example.org/namespace}elem')
+        buf = StringIO()
+        pickle.dump(qname, buf, 2)
+        buf.seek(0)
+        unpickled = pickle.load(buf)
+        self.assertEquals('{http://www.example.org/namespace}elem', unpickled)
+        self.assertEquals('http://www.example.org/namespace',
+                          unpickled.namespace)
+        self.assertEquals('elem', unpickled.localname)
+
 
 def suite():
     suite = unittest.TestSuite()
     suite.addTest(unittest.makeSuite(StreamTestCase, 'test'))
     suite.addTest(unittest.makeSuite(MarkupTestCase, 'test'))
-    suite.addTest(doctest.DocTestSuite(Markup.__module__))
+    suite.addTest(unittest.makeSuite(NamespaceTestCase, 'test'))
+    suite.addTest(unittest.makeSuite(QNameTestCase, 'test'))
+    suite.addTest(doctest.DocTestSuite(core))
     return suite
 
 if __name__ == '__main__':