Is there any chance that the fog will have also the influence on the billboards/planes?

What do you mean by billboards? Particles?

I meant billboards which we can generate as LOD but when I look closer I think that fog have the influence on it (I have low LOD distance for trees). Anyway I have on some models flat planes with textures and when fog is active I think that they are too bright/visible than another parts of model. You can see it in screen below or here: http://www.youtube.com/watch?v=z7TaAcHUcZA at 1:56.

Can you send me 1 model which looks incorrectly for you?

Sent it on PM.

what about textures and materials?

Well I looke closer into it and it's only when material has set Blend Light Tech.

I meant that I need those files

Ok, I didn't send it to you earlier because I thougth that this info will be enough

I've tested the building in WE game mode, and I don't have this problem (DX9/DX10, deferred/forward/simple renderers)

I'm not sure but in WE you use Sky.frac and Sky.atmosphericDensityExponent? Please try FogDraw function. I use this one and on both render mode - RM_CLOUD and RM_BLEND I have this issue. Is this because of some limitations of local fog?

please don't use FogDraw on both rendering modes RM_CLOUD and RM_BLEND (but only one) - you're rendering it twice

FogDraw will not affect blended meshes - it's impossible. so if you want smooth fog for blended meshes use either sky fog (Sky.frac and Sky.atmosphericDensityExponent) or global 'Fog'

Ok, thanks. I'll change my codes.