The correct course of action here would be to pick a UI toolkit, either GTK+ or Qt, and rewrite the OrbiterLinux portions that use the xlib calls, to use the toolkit calls, because xlib does NOT support unicode, and the amount of infrastructure required to graft such support on (think Pango) would be better spent basically just rewriting the code to use proper calls anyway. There are far too many weird little bugs with this code to continue using it in its current state.
Go for it.
-Thom