I noticed that too. Not that i found a solution. Here is a simple example (image 1): the two bars are the same, except the lower bar has UVs. In fact, every face in the lower bar is mapped to the same unit-square in UV space.. Crease angle is 80, which does not seem to work (in fact, only 0 stopped the smoothing). The actual UV coordinates seem to have no particular effect (i tried with random UVs, no difference). What does have an effect is the order of the faces (the lines with the f in the obj file), when i brought them into a random order (image 2), the smoothing error also seems to be irregular, but still persists. But face order should not have an effect on the appearence at all, so i would vote for a bug. Tested with poser 2010.