Difference between realistic viewport & render

[haanm002]

I just noticed a difference between what seems to be the ambient occlusion effect(?) in the realistic viewport and renderer. In the viewport it is much more pronounced, the shadows are darker. Note the part where the white (or at least it's supposed to be white) wall meets the floor, there is almost no shadow in the render.

It's just a simple scene with a skylight. Default scanline renderer with Light Tracer. Played with the settings, but couldn't come close to the viewport.

Now I really like the stronger effect in the viewport, how could I replicate it in the render?

[eric.paris]

How did you setup the ambient occlusion on your material?

Did you try to render with Mental Ray and global illumination?