3d snapping of line onto surface

 From:  3image
7967.1 
Hello,

I would like to draw a line in the 3d view from an outer point to the surface of an object. The line should snap to the object when it hits its surface. No problem in 2d views, but there is no snapping in 3d view at all. Please see the attachment. The lines doesn't snap to the surface but goes on and on behind it (dotted line).