http://bugs.winehq.org/show_bug.cgi?id=26503
--- Comment #4 from Dmitry Timoshkov dmitry@codeweavers.com 2011-03-22 00:25:59 CDT --- The problem is that windows with WS_DISABLED style completely ignore all input including mouse clicks (and therefore can't be activated) under Windows, while X11 happily brings this kind of windows in front. Wine prevents activation of such windows, but nothing more.
A workaround for application developers is avoid playing games with WS_DISABLED and use normal parent/owner z-order instead of desktop when creating top level windows.