problem baking occlusion in point cloud

[blue_riviera]

Hi,

I'm trying to bake occlusion into a point cloud in a surface shader.

I disabled the vm_hidden parameter in mantra (so in the interface "Enable Hiding" is off), and I still get some strange results.

As you can see in the attachment image, the pointcloud appears okay from the camera point of view (the pointcloud can be re-imported in a SOP network btw, which is quite cool).

However if you check the back side, it appears as if for some parts occlusion wasn't calculated at all, for others (teapot body), there is something that shows some resemblance

Any ideas on how to address this are appreciated

Thanks

imre