The problem is that it's vague, meaning that not even top lawyers interpret it the same way.
According to http://www.youtube.com/watch?v=Dy3zBZ4vI4E in such a case (according to the Vienna Convention) interpreted such laws requires the documents during the drafting phase of the convention. In case of ACTA these documents are secret even to the governments that have signed the agreement.
Paranoid yet?