Okay moron, lets see who has the clue, shall we?!
Quicktime's limitation is that it CANNOT stream anything other than downmixed 2ch PCM audio over it's optical port. THE ONLY FREAKING WAY to get 5.1 from quciktime is to have a SOUNDCARD i.e. the M-Audio one i posted with Discrete channels.
Not to mention why should you settle for inferior PL1 - PL2 / DTS when a good card will go proper digital ? By the way, they don't SIMULATE 5.1, they pre-dated 5.1.
Try doing some reading up on what Quicktime can / can't do with the optical hardware made by Texas Instruments in Mac's first before trying to shoot other people down. I thinkn i know a lot more about this stuff than you do.
Just one of many thousands of articles backing up what i said:
http://www.thismuchiknow.co.uk/?p=24