RE: Affects Version's
I only noted the ones I checked today.
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The Ambient Occlusion on the North face of a partial block is wrong.

In unmodded Minecraft this bug is easy to over look as it only affects the cobblestone wall. (as far as I could tell)

It becomes very easy to see on mod blocks that are using the standard renderer.

With Smooth Lighting off or minimum, the shadow is correct (left image)
but with it on maximum the shadow on the North face is wrong (right image)

The odd shadowing can bee seen just left of the cobblestone post, it can also be faintly seen on the post its self.

The mod block is to better show the shadow.
It is a very basic block, and uses the standard renderer.