Why do all gl-clients have a lock on gamma and contrast values?

My monitor is pretty old and has become darker by time, to even be able to use the bloody thing normally I need powerstrip or a similar program to tweak up the brightness... As you might figure I need an even brighter color-profile when playing Quake (because of the locks).

If you run software you can have it VERY bright so it can't be a anti-cheat thingy.

More gamma for next EzQuake please! This is just messing with players without cash for a new monitor...

I agree! My monitor is very old and dark too, although the min value of gamma (which gives maximum brightness, it is 0.3 for me) in fuhquake is just enough in the evening or at night, but not in daylight.

try with a new VGA-cable, at least it gave some extra mileage to some screens for me

Actually, it's an artificial restriction of windows NT/2k/XP. No clients have this restriction in Linux, or even win98/me.
ezquake has extra code to try and go as far as windows will let it. FTE has not (which is probably why people complain that gamma doesn't work... doh!). I don't know about other clients.