(OS X) Color component values of more than 680 only show as red

[Ben Fox-Moore]

I've noticed some strange behaviour with Ncurses 5.7 on my OS X 10.8 machine. If I try to create a custom color with (r,g,b) values (681,681,681), instead of showing up pretty much identical to COLOR_WHITE, it becomes a shade of red. (The same also applies to values above 681, always displaying the same shade of red.)

Here's some example code which has the problem: https://gist.github.com/InfernoZeus/5536379

and here's the result in OS X: http://i.imgur.com/GgaBP1p.png

First off, am I doing something wrong in my code? If not, is this a bug in OS X?

Thanks,

Ben