Hi,
if you have some knowledge about working with Apples Terminal Software and a SSH client under Mac OS X you don't need ANY hardware adapter!
You have to make an USB Bootstick for your Apple TV, after it is "cracked open" via software, you have to install nitoTV with a kernel extension for the composite signal and then you can use a standard rca-scart-connection to your MX :-)
The yellow video cable had to be plugged into the green output socket of your Apple TV. You will notice that you will have a immediately a black and white picture on your MX - even without hacking! For colour output the hacking is required :-)
You can connect the Apple TV via composite output (yellow videocable plus audio (L/R).
Another patch requires a HDMI-DVI-I-Adapter + a DVI-I-VGA-Adapter which should provide a simple hack. It didn't work for me, so I had to choose the long way and do it via software!
I don't know if the hack is possible with Windows, too!?
See the original thread:
http://forum.beoworld.org/forums/t/32328.aspx