If you set a screen's palette to a value above 0FF, exit the screen, and then reenter the screen, the first digit in the number (the 1 in 1FF, for example), will be reduced to 0. Closing and reopening ZQuest has this effect too.
This has only been tested in build 910, so I don't know whether or not this has been fixed yet.
Edit: The same thing happens to DMap palettes.