[Twisted-Python] listenTCP in a TAC

[Donal McMullan]

I've got a server application that listens on a port, and when clients
connect, spawns another TCP service on a random port that can live
from a few seconds, up to a day or two.

I had some problems getting this to work with
twisted.application.internet.TCPServer (my services wouldn't stop
listening when I'd finished with them) but it's working ok with plain
old reactor.listenTCP.

I don't really grok the TAC thing yet, or why there's a different
method for spawning servers within an Application. Is my listenTCP
approach bad practice for some reason that's not apparent to me?

Thanks!

Donal