RTSP on Windows

In our webcast solution we need to offer more streams at different bit rates (high, medium, low res, etc.). Our encoder can provide multiple streams at different bit rates, but it puts extra CPU load on the device which risks crashing the encoder. Today we can comfortably send 2 streams from the encoder – one goes to a Windows Media Server for our Windows clients and the other goes to a Darwin Media Server for our Mac users. The users stream from the broadcast servers via the RTSP protocol. This is highly important because we use Cisco WAAS devices in our office locations that can take the RTSP stream and split it at the office which limits the strain and number of streams on the WAN. However, we have had complaints from users that the single stream (500K bit rate) we send buffers too much which is why we need to offer some lower bit rate options. We saw your product and thought we could use it to take a single stream (maybe 2) and transcode it to 3 or 4 bit rates per OS and broadcast that to our users. In my initial testing it seems like this may only be possible for the Mac side (QuickTime Player 7) as I am not able to get RTSP to work with our Windows PCs (Windows Media Player). Is this possible or will RTSP streaming with your product only work with Mac?