Topic: Grant Kirkhope Voiced Donkey Kong In "Donkey Kong 64"

Here's what he had to say about it:

On the sound design front I can reveal that I was the voice of Donkey Kong, yes it’s me, actually Nintendo asked for the voice samples when they were making one of the Smash Brothers games, and they still used the DK Rap as well!

His official homepage (for the die hard fans!): http://grantkirkhope.com/granthome.html

You can even listen to music from his games on here so long as you have QuickTime installed. Just click the grey box and click "allow and remember".