Index: Lib/urllib.py
===================================================================
--- Lib/urllib.py	(revision 76700)
+++ Lib/urllib.py	(working copy)
@@ -95,6 +95,8 @@
 def urlcleanup():
     if _urlopener:
         _urlopener.cleanup()
+    _safemaps.clear()
+    ftpcache.clear()
 
 # check for SSL
 try:
Index: Lib/test/test_urllib.py
===================================================================
--- Lib/test/test_urllib.py	(revision 76700)
+++ Lib/test/test_urllib.py	(working copy)
@@ -6,6 +6,7 @@
 from test import test_support
 import os
 import mimetools
+import random
 import tempfile
 import StringIO
 
@@ -409,6 +410,13 @@
         self.assertEqual(urllib.quote_plus('alpha+beta gamma', '+'),
                          'alpha+beta+gamma')
 
+    def test_quote_leak(self):
+        # bug 5596 - highlight the refleak in the internal _safemaps cache
+        safe = ''.join(chr(random.randrange(128)) for i in '123456')
+        text = 'abcdefghijklmnopqrstuvwxyz'
+        result = urllib.quote(text, safe=safe)
+        self.assertEqual(result, text)
+
 class UnquotingTests(unittest.TestCase):
     """Tests for unquote() and unquote_plus()