The cause is that this thread has been moved (from *nix Security Discussions to General Chit Chat in this case), leaving a redirect in the original forum. That tends to set the date to 01-01-1970. You'll also notice that the front page won't show any additional posts anymore. A little bug indeed. Untill it's fixed, we won't use the 'move post with leaving a redirect'-function anymore...

Hope this helped.