diff --git a/Lib/email/test/test_email.py b/Lib/email/test/test_email.py
index 86ebaa58065..6320cd5d6cc 100644
--- a/Lib/email/test/test_email.py
+++ b/Lib/email/test/test_email.py
@@ -778,6 +778,20 @@ Received-2: from FOO.TLD (vizworld.acl.foo.tld [123.452.678.9]) by
 	hrothgar.la.mastaler.com (tmda-ofmipd) with ESMTP;
 	Wed, 05 Mar 2003 18:10:18 -0700
 
+""")
+
+    def test_string_headerinst_eq(self):
+        h = '<15975.17901.207240.414604@sgigritzmann1.mathematik.tu-muenchen.de> (David Bremner\'s message of "Thu, 6 Mar 2003 13:58:21 +0100")'
+        msg = Message()
+        msg['Received-1'] = Header(h, header_name='Received-1',
+                                   continuation_ws='\t')
+        msg['Received-2'] = h
+        self.assertEqual(msg.as_string(), """\
+Received-1: <15975.17901.207240.414604@sgigritzmann1.mathematik.tu-muenchen.de>
+	(David Bremner's message of "Thu, 6 Mar 2003 13:58:21 +0100")
+Received-2: <15975.17901.207240.414604@sgigritzmann1.mathematik.tu-muenchen.de>
+	(David Bremner's message of "Thu, 6 Mar 2003 13:58:21 +0100")
+
 """)