I remembered I read something about fake dynamic lighting...
... I found that here: (
DO NOT LINK) h t t p s : / / openarena . wikia . com/wiki/Mapping_manual/Advanced_lighting#Light_styles (taken from here:
http://www.leveldk.co.uk/tut7.htm)
I have not tried that, but it looks like it's a limted feature, to be used for things like the flickering light emitted by a torch... I suppose it's not useful for what Fromhell needs.
However, do you know some map which uses such trick? I'm a bit curious...
By the way, I noticed OA 0.8.1 pak0.pk3 contains "q3map2_void3.shader" and "q3map2_void4.shader".... useless leftover from previous OA releases which included a couple of maps which used this trick, maybe?