diff --git a/Lib/test/test_smtplib.py b/Lib/test/test_smtplib.py
index dab4fe0..e2b9b06 100644
--- a/Lib/test/test_smtplib.py
+++ b/Lib/test/test_smtplib.py
@@ -1,4 +1,5 @@
 import asyncore
+import email.utils
 import socket
 import threading
 import smtpd
@@ -75,6 +76,15 @@
         smtp = smtplib.SMTP("%s:%s" % (HOST, PORT))
         smtp.sock.close()
 
+    def testNotConnected(self):
+        # Test various operations on an unconnected SMTP object that
+        # should raise exceptions (at present the attempt in SMTP.send
+        # to reference the nonexistent 'sock' attribute of the SMTP object
+        # causes an AttributeError)
+        smtp = smtplib.SMTP()
+        self.assertRaises(AttributeError, smtp.ehlo)
+        self.assertRaises(AttributeError, smtp.send, 'test msg')
+
     def testLocalHostName(self):
         # check that supplied local_hostname is used
         smtp = smtplib.SMTP(HOST, PORT, local_hostname="testhost")
@@ -82,9 +92,11 @@
         smtp.sock.close()
 
     def testNonnumericPort(self):
-        # check that non-numeric port raises ValueError
+        # check that non-numeric port raises socket.error
         self.assertRaises(socket.error, smtplib.SMTP,
                           "localhost", "bogus")
+        self.assertRaises(socket.error, smtplib.SMTP,
+                          "localhost:bogus")
 
     def testTimeoutDefault(self):
         # default
@@ -110,9 +122,9 @@
         smtp.sock.close()
 
 
-# Test server using smtpd.DebuggingServer
-def debugging_server(serv_evt, client_evt):
-    serv = smtpd.DebuggingServer(("", 0), ('nowhere', -1))
+# Test server thread using the specified SMTP server class
+def debugging_server(server_class, serv_evt, client_evt):
+    serv = server_class(("", 0), ('nowhere', -1))
     global PORT
     PORT = serv.getsockname()[1]
 
@@ -148,11 +160,12 @@
 MSG_BEGIN = '---------- MESSAGE FOLLOWS ----------\n'
 MSG_END = '------------ END MESSAGE ------------\n'
 
-# Test behavior of smtpd.DebuggingServer
-# NOTE: the SMTP objects are created with a non-default local_hostname
-# argument to the constructor, since (on some systems) the FQDN lookup
-# caused by the default local_hostname sometimes takes so long that the
+# NOTE: Some SMTP objects in the tests below are created with a non-default
+# local_hostname argument to the constructor, since (on some systems) the FQDN
+# lookup caused by the default local_hostname sometimes takes so long that the
 # test server times out, causing the test to fail.
+
+# Test behavior of smtpd.DebuggingServer
 class DebuggingServerTests(TestCase):
 
     def setUp(self):
@@ -163,7 +176,7 @@
 
         self.serv_evt = threading.Event()
         self.client_evt = threading.Event()
-        serv_args = (self.serv_evt, self.client_evt)
+        serv_args = (smtpd.DebuggingServer, self.serv_evt, self.client_evt)
         threading.Thread(target=debugging_server, args=serv_args).start()
 
         # wait until server thread has assigned a port number
@@ -189,12 +202,42 @@
         smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
         smtp.quit()
 
-    def testEHLO(self):
+    def testNOOP(self):
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+        expected = (250, 'Ok')
+        self.assertEqual(smtp.noop(), expected)
+        smtp.quit()
+
+    def testRSET(self):
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+        expected = (250, 'Ok')
+        self.assertEqual(smtp.rset(), expected)
+        smtp.quit()
+
+    def testNotImplemented(self):
+        # EHLO isn't implemented in DebuggingServer
         smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
         expected = (502, 'Error: command "EHLO" not implemented')
         self.assertEqual(smtp.ehlo(), expected)
         smtp.quit()
 
+    def testVRFY(self):
+        # VRFY isn't implemented in DebuggingServer
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+        expected = (502, 'Error: command "VRFY" not implemented')
+        self.assertEqual(smtp.vrfy('nobody@nowhere.com'), expected)
+        self.assertEqual(smtp.verify('nobody@nowhere.com'), expected)
+        smtp.quit()
+
+    def testSecondHELO(self):
+        # check that a second HELO returns a message that it's a duplicate
+        # (this behavior is specific to smtpd.SMTPChannel)
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+        smtp.helo()
+        expected = (503, 'Duplicate HELO/EHLO')
+        self.assertEqual(smtp.helo(), expected)
+        smtp.quit()
+
     def testHELP(self):
         smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
         self.assertEqual(smtp.help(), 'Error: command "HELP" not implemented')
@@ -214,6 +257,7 @@
         self.assertEqual(self.output.getvalue(), mexpect)
 
 
+# test response of client to a non-successful HELO message
 class BadHELOServerTests(TestCase):
 
     def setUp(self):
@@ -243,9 +287,146 @@
         self.assertRaises(smtplib.SMTPConnectError, smtplib.SMTP,
                             HOST, PORT, 'localhost', 3)
 
+
+sim_users = {'Mr.A@somewhere.com':'John A',
+             'Ms.B@somewhere.com':'Sally B',
+             'Mrs.C@somewhereesle.com':'Ruth C',
+            }
+
+sim_lists = {'list-1':['Mr.A@somewhere.com','Mrs.C@somewhereesle.com'],
+             'list-2':['Ms.B@somewhere.com',],
+            }
+
+# Simulated SMTP channel & server
+class SimSMTPChannel(smtpd.SMTPChannel):
+    def smtp_EHLO(self, arg):
+        resp = '250-testhost\r\n' \
+               '250-EXPN\r\n' \
+               '250-SIZE 20000000\r\n' \
+               '250-STARTTLS\r\n' \
+               '250-DELIVERBY\r\n' \
+               '250 HELP'
+        self.push(resp)
+
+    def smtp_VRFY(self, arg):
+#        print '\nsmtp_VRFY(%r)\n' % arg
+
+        raw_addr = email.utils.parseaddr(arg)[1]
+        quoted_addr = smtplib.quoteaddr(arg)
+        if raw_addr in sim_users:
+            self.push('250 %s %s' % (sim_users[raw_addr], quoted_addr))
+        else:
+            self.push('550 No such user: %s' % arg)
+
+    def smtp_EXPN(self, arg):
+#        print '\nsmtp_EXPN(%r)\n' % arg
+
+        list_name = email.utils.parseaddr(arg)[1].lower()
+        if list_name in sim_lists:
+            user_list = sim_lists[list_name]
+            for n, user_email in enumerate(user_list):
+                quoted_addr = smtplib.quoteaddr(user_email)
+                if n < len(user_list) - 1:
+                    self.push('250-%s %s' % (sim_users[user_email], quoted_addr))
+                else:
+                    self.push('250 %s %s' % (sim_users[user_email], quoted_addr))
+        else:
+            self.push('550 No access for you!')
+
+
+class SimSMTPServer(smtpd.SMTPServer):
+    def handle_accept(self):
+        conn, addr = self.accept()
+        channel = SimSMTPChannel(self, conn, addr)
+
+    def process_message(self, peer, mailfrom, rcpttos, data):
+        pass
+
+
+# Test various SMTP & ESMTP commands/behaviors that require a simulated server
+# (i.e., something with more features than DebuggingServer)
+class SMTPSimTests(TestCase):
+
+    def setUp(self):
+        self.serv_evt = threading.Event()
+        self.client_evt = threading.Event()
+        serv_args = (SimSMTPServer, self.serv_evt, self.client_evt)
+        threading.Thread(target=debugging_server, args=serv_args).start()
+
+        # wait until server thread has assigned a port number
+        n = 500
+        while PORT is None and n > 0:
+            time.sleep(0.01)
+            n -= 1
+
+        # wait a little longer (sometimes connections are refused
+        # on slow machines without this additional wait)
+        time.sleep(0.5)
+
+    def tearDown(self):
+        # indicate that the client is finished
+        self.client_evt.set()
+        # wait for the server thread to terminate
+        self.serv_evt.wait()
+
+    def testBasic(self):
+        # smoke test
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+        smtp.quit()
+
+    def testEHLO(self):
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+
+        # no features should be present before the EHLO
+        self.assertEqual(smtp.esmtp_features, {})
+
+        # features expected from the test server
+        expected_features = {'expn':'',
+                             'size': '20000000',
+                             'starttls': '',
+                             'deliverby': '',
+                             'help': '',
+                             }
+
+        smtp.ehlo()
+        self.assertEqual(smtp.esmtp_features, expected_features)
+        for k in expected_features:
+            self.assertTrue(smtp.has_extn(k))
+        self.assertFalse(smtp.has_extn('unsupported-feature'))
+        smtp.quit()
+
+    def testVRFY(self):
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+
+        for email, name in sim_users.items():
+            expected_known = (250, '%s %s' % (name, smtplib.quoteaddr(email)))
+            self.assertEqual(smtp.vrfy(email), expected_known)
+
+        u = 'nobody@nowhere.com'
+        expected_unknown = (550, 'No such user: %s' % smtplib.quoteaddr(u))
+        self.assertEqual(smtp.vrfy(u), expected_unknown)
+        smtp.quit()
+
+    def testEXPN(self):
+        smtp = smtplib.SMTP(HOST, PORT, local_hostname='localhost', timeout=3)
+
+        for listname, members in sim_lists.items():
+            users = []
+            for m in members:
+                users.append('%s %s' % (sim_users[m], smtplib.quoteaddr(m)))
+            expected_known = (250, '\n'.join(users))
+            self.assertEqual(smtp.expn(listname), expected_known)
+
+        u = 'PSU-Members-List'
+        expected_unknown = (550, 'No access for you!')
+        self.assertEqual(smtp.expn(u), expected_unknown)
+        smtp.quit()
+
+
+
 def test_main(verbose=None):
     test_support.run_unittest(GeneralTests, DebuggingServerTests,
-                              BadHELOServerTests)
+                              BadHELOServerTests, SMTPSimTests)
 
 if __name__ == '__main__':
     test_main()