You've got to be kidding me! or The Holocaust existed, so what?

According to this article that I just this moment read (Ice Dancing is on on the Olympics and I have no interest in it...neither does LG for that matter but neither of us has changed the channel yet) a British historian named David Irving was sentenced to three years in prison in Austria for having denied that the Holocaust ever happened. I know nothing about this case beyond what is in this article, but it seems to me that a person in a free country cannot be arrested for only saying something. Something which he now believes is wrong. In court he admitted that he was wrong, that the Holocaust actually happened. This verdict/sentencing worries me. Please comment if you know anything more about this (I'm looking at you Dr. Actually).