diff -r 06244031b608 Lib/test/test_builtin.py
--- a/Lib/test/test_builtin.py	Thu Aug 22 17:53:16 2013 +0300
+++ b/Lib/test/test_builtin.py	Fri Aug 23 16:17:32 2013 +0300
@@ -1287,6 +1287,13 @@
         a = {}
         a[0] = a
         self.assertEqual(repr(a), '{0: {...}}')
+        if have_unicode:
+            class T(object):
+                def __repr__(self):
+                    return unichr(0x20ac)
+            r = repr(T())
+            self.assertEqual(r, r'\u20ac')
+            self.assertIs(type(r), str)
 
     def test_round(self):
         self.assertEqual(round(0.0), 0.0)
diff -r 06244031b608 Objects/object.c
--- a/Objects/object.c	Thu Aug 22 17:53:16 2013 +0300
+++ b/Objects/object.c	Fri Aug 23 16:17:32 2013 +0300
@@ -384,7 +384,7 @@
 #ifdef Py_USING_UNICODE
         if (PyUnicode_Check(res)) {
             PyObject* str;
-            str = PyUnicode_AsEncodedString(res, NULL, NULL);
+            str = PyUnicode_AsEncodedString(res, NULL, "backslashreplace");
             Py_DECREF(res);
             if (str)
                 res = str;