CIV IV and fog of war problem

[trinity]

Hi,
I can play Civ IV fine but I have an annoying problem. When I start a game, I can see all the map (I see rivers and forest in black but I should not see them!). I use cedega 5.1 (demo). I installed patch 1.52. My video card is a Geforce 4 MX 4000. If I use windowsXP I don't have this kind of problem. So I want to ask here if somebody else has this problem and how can I fix it?!

Thanks!