Detailed explanation of the EU directive can be found in a related thread: EU customers with national VAT numbers: should VAT be charged?
As Gary Wilkinson from the European Commission DG Taxation and Customs Union wrote,
However, since this Community legislation is based on a Directive, each Member State is responsible for the transposition of these provisions into national legislation and their correct application within its territory. In the light of this and the basic principles of subsidiarity, national tax administrations have the principal responsibility for informing their taxable persons about the interpretation and application of these provisions.
Therefore, I would suggest that you contact the relevant national tax administration direct, in order to obtain a precise, complete and binding answer to your query.
[Edited at 2010-02-02 13:12 GMT]