'Test that the string "ESMTP" does appear in the ESMTP server\'s
greeting since L{smtp.ESMTP} does support the SMTP extensions which
that advertises to the client.'

def testESMTPGreetingExtended(self):

    s = smtp.ESMTP()
    t = StringTransport()
    s.makeConnection(t)
    s.connectionLost(error.ConnectionDone())
    self.assertIn('ESMTP', t.value())
