diff -r 771f28686022 Lib/test/test_cmd_line.py
--- a/Lib/test/test_cmd_line.py	Thu Nov 22 23:56:51 2012 +0100
+++ b/Lib/test/test_cmd_line.py	Fri Nov 23 10:57:47 2012 +0200
@@ -118,9 +118,7 @@
 
 
     def test_unknown_options(self):
-        # Add "without='-E'" to prevent _assert_python append env_vars -E
-        # which changes the output of stderr
-        rc, out, err = assert_python_failure('-z', without='-E')
+        rc, out, err = assert_python_failure('-z')
         self.assertIn(b'Unknown option', err)
         self.assertEqual(err.splitlines().count(b'Unknown option: -z'), 1)
         self.assertEqual(b'', out)
diff -r 771f28686022 Modules/main.c
--- a/Modules/main.c	Thu Nov 22 23:56:51 2012 +0100
+++ b/Modules/main.c	Fri Nov 23 10:57:47 2012 +0200
@@ -264,6 +264,7 @@
 
     /* Hash randomization needed early for all string operations
        (including -W and -X options). */
+    _PyOS_opterr = 0;  /* prevent printing the error in 1st pass */
     while ((c = _PyOS_GetOpt(argc, argv, PROGRAM_OPTS)) != EOF) {
         if (c == 'm' || c == 'c') {
             /* -c / -m is the last option: following arguments are
diff -r 771f28686022 Python/getopt.c
--- a/Python/getopt.c	Thu Nov 22 23:56:51 2012 +0100
+++ b/Python/getopt.c	Fri Nov 23 10:57:47 2012 +0200
@@ -41,7 +41,7 @@
 
 void _PyOS_ResetGetOpt(void)
 {
-    _PyOS_opterr = 0;   /* prevent printing the error in 2nd loop in main.c */
+    _PyOS_opterr = 1;
     _PyOS_optind = 1;
     _PyOS_optarg = NULL;
     opt_ptr = "";