Strange Shadow

The shadow you usually see under you has a strange effect when flying. I'm not quite sure how to explain it, so I'm going to add a screenshot.

I expected no shadow..?

There was a shadow ABOVE me when I was flying near an object.

Steps to Reproduce:
1. fly near a surface, just under it but not um... under it?
2. press f5 and look for the shadow.
3. Look at the shadow.