diff -r cb5317ceca84 Lib/test/test_unicode.py
--- a/Lib/test/test_unicode.py	Thu Jul 24 13:16:45 2008 +0200
+++ b/Lib/test/test_unicode.py	Fri Jul 25 14:33:32 2008 +0200
@@ -531,6 +531,10 @@
         self.assertRaises(UnicodeError, unicode, '+3ADYAA-', 'utf-7')
 
         self.assertEqual(unicode('+3ADYAA-', 'utf-7', 'replace'), u'\ufffd')
+        
+        # Issue #2242: crash on some Windows/MSVC versions
+        self.assertRaises(UnicodeDecodeError, '+\xc1'.decode, 'utf-7')
+
 
     def test_codecs_utf8(self):
         self.assertEqual(u''.encode('utf-8'), '')
diff -r cb5317ceca84 Objects/unicodeobject.c
--- a/Objects/unicodeobject.c	Thu Jul 24 13:16:45 2008 +0200
+++ b/Objects/unicodeobject.c	Fri Jul 25 14:33:32 2008 +0200
@@ -1523,7 +1523,7 @@
     while (s < e) {
         Py_UNICODE ch;
         restart:
-        ch = *s;
+        ch = (unsigned char) *s;
 
         if (inShift) {
             if ((ch == '-') || !B64CHAR(ch)) {