TRUFORM Tesselation with PNTriangles

Hello,

i made a tool to load PLG-files(a type of indexed facesets). It works fine.
I used an VertexArray to draw the triangles.
Afte that and after calculating all vertex-normals i tried to use glPNTrianglesiATI to tesselate and to get a smother surface on all objets. But the result of enabling PN-TRIANGLES look very strange. And if i switch to wireframe the hole Application crashes.
There is an PN_Triangles example on the ATI-Website which works just perfect with the same ati-library and nearly the same code.

Could it be that the faces or vertices need to be in a special order?

Thanks,
Baerbel