How do you find the name of the actual swf playpath to download?

[puterboy]

When I want to watch the stream in my browser, I use a URL of form:
http://www.blahblah/mwplayer.swf

RTMP downloaders like Moyea are able to figure out the actual playpath location using the URL.

However, rtmpdump seems to need the actual playpath of the specific file.

Is there any way either using rtmpdump or some 3rd party script or program to figure out the name of the file that needs to be streamed?
I assume that somehow/somewhere mwplayer.swf must encode or point to the actual file but it is a binary file.

Thanks