Hi.
I know this is an old topic but I am currently experiencing the same issue with enscape 3.5. I alreaday tried everything I know to fix the problem. I even tried rendering just a few white boxes with no texture at all just the sun for the lights. But I'm still getting the same result. Its like producing a very dark shadow from the first frame. Like Akuma shadow in street fight when he moves, if you know what I mean.
Hope someone will be able to help me.