diff --git a/Lib/test/test_opcodes.py b/Lib/test/test_opcodes.py
index d7d1673..7985bf6 100644
--- a/Lib/test/test_opcodes.py
+++ b/Lib/test/test_opcodes.py
@@ -102,6 +102,12 @@
         g = eval('lambda a=1: None')
         self.assertNotEquals(f, g)
 
+    def test_modulo_of_string_subclasses(self):
+        class MyString(str):
+            def __mod__(self, value):
+                return 42
+        self.assertEqual(MyString() % 3, 42)
+
 
 def test_main():
     run_unittest(OpcodeTest)