Problem with Fog

I’m programming with C++Builder and using third party OpenGL-components for the C++Builder. With these I have created a Para/Hanggliding simulator (www.aeroglider.de). But these components creating the fog only in z-world-direction. Any idea, how this error can be done generally? I have got the source code of the components and I want to correct the bug, but in the red/blue book I can’t find anything.

hi markus,
aeroglider looks nice!
check out druids gl-journal,
i think ive read something about volumed fog there…hope this helps