Ah Peter, I do not think Irving should be jailed only for his arrogance and stupidity. (I freely admit that is enough to wipe out any lingering trace of sympathy I had for him though). Irving effectively dared the Austrians to imprison him. I actually agree with most of what you say about freedom of speech. Indeed, the way we react to those, whom we dislike is a good test of our commitment to it.
David Irving is not fighting for freedom of speech. He is fighting for freedom to lie. That is not a freedom I will ever support. He deserves that "freedom" no more than the other racists, who shout lies and try to provoke violence against ethnic groups. He has had his day in court. Overwhelming evidence of lying has been presented against him. We reach the point where the verbal harrasment of a woman, by a stalker, needs to be evaluated for the effect, which it will have on the woman. My view is that David Irving has crossed a similar line. It appears to be the view of the Austrian court too. Irving has essentially told the Austrians that their law stinks. They ignored it once. This was not possible when he returned.