Live encoding from an internet source

hello.
i need a software able to do this :
getting in input a video/audio live stream from an url (like a webtv) and
outputting it to another live stream, but in Flash format (playable with a Flash player).

I tried with Flash Video Encoder + Flash Media Encoder + Flash Media Server, but they can not do it.
They only take local files or webcam and microphone as input, but internet sources are not supported.

If such a program does not exist , i would want a program that simulates a webcam, in other words, that creates a virtual webcam.
It should take as input the live stream from the internet and play at the video comes from a physical webcam.

the same applies for the audio part, i need also a program that creates a virtual microphone that gets the audio from the same url source.

Then, i could use these virtual webcam and microphone with Flash Media Encoder and Flash Media Server.

is there some program that can help?