I can confirm this for the NTSC-version, as I just tried this myself. Weird, it must be an oversight or something.
I noticed that a few years back, but I never brought it up because I thought it was no big deal. I mean, we all see stuff in real clouds anyway. =P
It's a well known phenomenon called Pareidolia - http://en.wikipedia.org/wiki/Pareidolia Basically, the human brain likes to make patterns out of chaos, which is why you get people who see Jesus in toast burns, Lenin in shower curtains, and Homer Simpson in video game cloud formations. =P
So, wait... does that mean that every music command in the game's cutscenes is given through the SUBTITLE-Files? O_o
I don't know if this is old, but I found acts 3, 4 and beyond in HPZ (Sonic 2). Here's the video. http://www.youtube.com/watch?v=4ReE-dNNYac I'll go further another time.