There IS a Max script for this that adds a Edit Normals modifier to the stack containing the computed vert normals. We use it all the time: http://www.polycount.com/forum/showpost.php?p=1690226&postcount=48
Warren; As far as I can tell, that's an area weighting, rather than angle weighting script? Here's some comparison images between weighting methods on a mesh like that; The end normals would be cleaner if I hadn't left caps on them, whoops. And the effect would still be there if I had split the smoothing along the corner…