I don't know any other way other than the pure maths way: http://en.wikipedia.org/wiki/Line-plane_intersection
Of course that deals with and infinite plane and an infinite line, if you are looking for the intersection of a line segment and a confined plane, you would have to verify if the hypothetical point of intersection, if it exists, lies within the sets of points of each object. You could also look up ray casting methods/algorithms to test if an infinite line collides with any of the plane's faces. I'm not sure if any part of Away3D currently implements this, or even if the methods are made externally accessible if existing. Hope it helps, Li
