Bake result problem on a dark material

Hi there, I am having a problem with this baking output.
Ver 2.7, Blender render, the material is a simple black with a specular
Baked 200 samples, RGBA and 16 bit color depth. I tried messing with other settings but still the same result: the smooth between the different shades is missing. When a lighter color is applied the result is just fine, but appears only when its a darker color.

Is anyone familliar with this? I usually use cycles but for this simple material the whole scene and lighning were set up in blender render.
Please let me know if any other info is needed.