Could you please post it so we can all listen to it???

I think http://oddworldlibrary.net/media/oswsubliminal.wav is the full reverse message. I can't check on this computer as it doesn't have any sound, but I'm confident it's what you're after.

I'll just add that credit goes to Boneho Chane for first noticing the reverse message, to Mr Pottymouth for first supplying the recording in reverse, and to Cort for this file.

Yup, its there.