It looks like the swf is still trying to access the rtmp
channel. Once you've made the updates to your configuration file,
you should restart the server. Also, because a bug in Beta 3, which
is now fixed, you'll need to force a recompile of your swf on the
next request by calling xxx.mxml?recompile=true.
One thing to note - if you're trying to get updates from the
server, you'll want to be sure that your http channel is set for
polling. Otherwise, you'll be able to send updates to the server
but won't receive any.