Does Chimp x Gorilla Hybrid Exist?

Darren Naish at Tetrapod Zoology posted an interesting post about chimp x gorilla hybrid or the koolo-kamba. Do you think such hybrid exists or these individuals just display a range of "genetic variation" previously unknown to science? Check out Darren's post now, The Yaounde Zoo mystery ape and the status of the Kooloo-Kamba.