Not getting the exact colors on 16 bpp display

["Daniel Solaz" <dsolaz sistelcom com>]

Hello.
I don't get the exact colors I want on my 16 bpp display. Specifying
{0.75,0.75,0.75} should give #BFBFBF, as it does on a 32 bpp display,
but I'm getting #B8BCB8, which is darker enough to look different.
It's not that I consider this a bug (I'm going to plug 2 extra megs into
my graphics card next week, anyway). But the same thing happens with
some other apps such as XCalc, and other toolkits such as Trestle (which
uses the 0.0-1.0 color model as well). Anyone knows exactly why?
-Daniel
oops: I've got a Matrox Millennium, XFree 3.3.1 SVGA X Server, GTK
0.99.10