Just so that it doesnt get lost in the archives... http://mail.xfce.org/pipermail/xfce4-dev/2014-February/030611.html
Created attachment 5376 Use time_t/suseconds_t instead of long patch ready for git-am
Thanks for the patch, merged it in: http://git.xfce.org/xfce/xfwm4/commit/?id=8448703965b25c1ee97410aa463d789a43a6c771