tesselated objects surface normals

hi all,

I need to create an tesselated objects, I’m using the tesselator and shapes visually are satisfying but when it comes to selection everthing is getting spoiled. After debbuging I saw that the tesselator creates the object and “gluTessNormal” only governs the winding direction of vertices but not assigning the normal vector for the created objects. Each polygon is convex and and the shape is pretty simple created from rectangles (first contour is projected on X-Y plane and then is extruded in Z direction) only the bottom part(horizontal) of object is selectable but the extruded sides (vertical surfaces) are not.

May I use glNormal* procedure to specify the surface normals for object created with the tesselator or do I have to use quads?

Help in advance will be muh appreciated