SDS Corners
From K-3D
I have very little information on what variable sharpness corners are supposed to look like. The only reference I found is
http://www.animallogic.com/research/maxman/onlinedocs/Tutorials/subdivs.html
I have manually reproduced this effect by adding some faces around corners:
Detail of the added edges:
Hint: to achieve this effect, use the LinkPoints tools.
Bart Janssens <bart dot janssens at lid dot kviv dot be>