Known issue, about the server =/ sorry, it's just really cheap hosting.
My other server is very space-limited and could disappear at any second
Edit: now that brix have been s**t, I share the spoilerific .cap
http://www.udec.cl/~jfuente_alba/3dfog.cap
Double Edit: Found an error in the math, fog looks much deeper now, specially when turning =)