Rendering shadows on the edges

I have been playing with lightning and shadows. I added Directional Light Shadow Renderer to Dircect Light and jME render this:

Shadows are rendered few centimeters under the edges, I tried also Directional Light Shadow Filter, but it does same thing. Then I try to incrase the map size and number of passes, it goes better, but still shadows doesn’t render on the edges.

And now you can see on the second picture what is happening on the rear window. I think that is connected with edges rendering problem.
What do I do wrong, or what filter could solve this problem?
Note: I’m using materials from blender, only materials that I use for lights on cars are created in jME.
Thank you.