CD-DA on VCD's

[Big_Jit]

I was just looking at the CD-Da Part on the VCD specifications sheet on this site and how it says CD-DA optional. Does that mean that the dvd player will optionally play the cd audio on that part of the disc or can you set up your VCD menu's to play cd audio...

[Big_Jit]

Let me re-phrase this...

What is the CDDA part of the VCD for?... I know it says optional. But How is it used. I was wanting to create some Music Video CD's and I like to put the MP3's on the Disc if I have the space to spare. But is there something special about the CDDA folder on VCD's