[Twisted-Python] How to get port when using application

Hello, I am going to use application and I have a question, I have a server that needs to get a free port, before I would do this : ... port = reactor.listenTCP(0, f).getHost().port ... and now with application all I could find to do the equivilent was : ... t = internet.TCPServer(0, tcpFactory) port = p._getPort()._realPortNumber ... the problem is that this isn't very clean as I'm accessing protected members. Is there a better way of doing this? Thank you, Gabriel