diff --git a/Lib/test/test_itertools.py b/Lib/test/test_itertools.py
index 4b631dd..6898725 100644
--- a/Lib/test/test_itertools.py
+++ b/Lib/test/test_itertools.py
@@ -371,6 +371,7 @@
 
         # test values of n
         self.assertRaises(TypeError, tee, 'abc', 'invalid')
+        self.assertRaises(ValueError, tee, [], -1)
         for n in xrange(5):
             result = tee('abc', n)
             self.assertEqual(type(result), tuple)