I meant to post this awhile back:
In case you want to play mp4 (aac/apple quicktime) files on your PPC and you get that Error message stating that that codec was removed, etc. then you'll want this file. (It's when you get the picture but no sound)
Just download and install. It was pulled from TCMP because of Apple and copyright issues.
*Note: You will need
The Core Media Player for this. It will not work with Windows Media Player