Maybe a wrong material settup in Kerkythea (Answer: No, bad topology)

[micheus]

It looks like for Pov-Ray you are showing that without normals looks worse.

Yeah, but I think that could be a feature.
Not exporting the normal make POV-Ray to render flat faces (triangles).

KT seems to work better with that povmaniac said. On my view point it's doing the right thing by looking the faces with normals pointing to the camera and do not using the faces with opposed normals to smooth them (in this case). Probably it do that to the those faces if I put a reflective object behind of the leaf. I'm going to try.

By the other way, POV-Ray deal better with the alpha texture, since I don't need to use any mask to get it correctly rendered.