The European court has ruled that the Netherlands is not allowed to make diesel particle filters compulsory on new cars. Instead the Netherlands has to wait till the end of 2008. Making the filter compulsory in the Netherlands would be unfair the the manufacturers because they would have to make changes to the product only for the Dutch market.
The Dutch government wanted to make the filters compulsory earlier because of the problems the Netherlands have with the European rule on clean air. Despite the ruling, 60% of the cars sold in the Netherlands which are equipped with diesel engines are also equipped with a particle filter.
One example of how the market can react quicker than the European politicians and how Europe should not interfere with the activities in the individual countries.