def listenSSL(port, factory, contextFactory, backlog=50, interface=''):
    """
        Connects a given protocol factory to the given numeric TCP/IP port.
        The connection is a SSL one, using contexts created by the context
        factory.

        @param port: a port number on which to listen

        @param factory: a L{twisted.internet.protocol.ServerFactory} instance

        @param contextFactory: a L{twisted.internet.ssl.ContextFactory} instance

        @param backlog: size of the listen queue

        @param interface: the hostname to bind to, defaults to '' (all)
        """
