diff -r f6c85df15874 Lib/json/tests/test_decode.py
--- a/Lib/json/tests/test_decode.py	Tue May 03 20:41:48 2011 +0300
+++ b/Lib/json/tests/test_decode.py	Tue May 03 22:16:58 2011 +0300
@@ -26,7 +26,8 @@
     def test_empty_objects(self):
         self.assertEqual(json.loads('{}'), {})
         self.assertEqual(json.loads('[]'), [])
-        self.assertEqual(json.loads('""'), "")
+        self.assertEqual(json.loads('""'), u"")
+        self.assertIsInstance(json.loads('""'), unicode)
 
     def test_object_pairs_hook(self):
         s = '{"xkd":1, "kcw":2, "art":3, "hxm":4, "qrt":5, "pad":6, "hoy":7}'
diff -r f6c85df15874 Modules/_json.c
--- a/Modules/_json.c	Tue May 03 20:41:48 2011 +0300
+++ b/Modules/_json.c	Tue May 03 22:16:58 2011 +0300
@@ -382,10 +382,10 @@
 static PyObject *
 join_list_string(PyObject *lst)
 {
-    /* return ''.join(lst) */
+    /* return u''.join(lst) */
     static PyObject *joinfn = NULL;
     if (joinfn == NULL) {
-        PyObject *ustr = PyString_FromStringAndSize(NULL, 0);
+        PyObject *ustr = PyUnicode_FromStringAndSize(NULL, 0);
         if (ustr == NULL)
             return NULL;