Last week, we had the author of TDD for a Shopping Website LiveProject. Friday at 11am Ranch time, Steven Solomon will be hosting a live TDD session just for us. See for the agenda and registration link
How isn't it working? Is there an error message, bad response code, no response at all? It's possible that the server you're hitting just doesn't respond to POST requests to that URL.
That means Bad Request. That doesn't mean that POST is not supported; that would trigger a 405 error (Method Not Allowed). So something is wrong with the data you send.
I think this is beyond just I/O so I'll steal ( ) this thread away to our Sockets and Internet Protocols forum.