(adsbygoogle = window.adsbygoogle || []).push({}); Before the 1.07 update for Black Ops, if you were playing zombies and were to dive on someone else it would cause both of those players to get downed.
Since the 1.07 patch and with ascension they have fixed/changed it and now you no longer get downed.
I think this is to prevent people downing themselves when using PhD Flopper.



EDIT: I just tried again and got downed, hmmm...?

Im pretty sure its supposed to be an easter egg, since it starts a little sound clip whenever it happens. So its not a glitch Treyarch meant to put that in the game

No its still there I did it by accident today