We are using server side action script to perform authentication to block
certain users from streaming our videos.

We want to display a meaningful error message on the web page/flash player if
the authentication fails. The manual briefly mentions that error status codes
can be used for error-handling scripts. Can someone provide some more details?
In our case, we want to have a custom error status code and somehow the status
code can be propagated to the client such that the appropriate message can be
shown. Thanks.