According to the Daily Mail anyway. The BBC lipreader came up with something else on Newsnight that went something like 'An ugly death for you and your family'. There was also a long numbered list of speculative insults some referring to Zidane's mother who is apparently ill. The Italian perpetrator is keeping quiet indicating a pretty serious taunt. I suppose we'll never know, what would be interesting to know was how premeditated, how orchestrated was it? Did someone research his life to find out what buttons to push?
Official Zidane site