landclass problem with ground2k2

[tshikwara]

I was wondering if anyone could help me with this problem. I have been working on some scenery in Ground2k2 but have noticed that the night textures/ land class is incorrect. I have made some semidesert scenery, but at night, it lights up like a city!! ON the other hand, an area of small city I made does not light up at night at all, and is in perpetual darkness!! Does any one have any ideas on how to fix this???
Cheers