Hi all, I just this morning installed xmonad on my computer at work, and I've run into some bugginess in focus-follows-mouse on this computer: it doesn't work! The only difference that seems notable is that this is a 64-bit machine, while my home computer is 32-bit. In any case, the bugginess is just tha focus doesn't follow mouse. After some tracing, I discovered that the problem was that the ev_mode is weird. The following debug code in Main (right before the trace at the bottom) reveals that handle e@(CrossingEvent {ev_window = w, ev_event_type = t}) | t == enterNotify && ev_detail e /= notifyInferior = trace ("mode must be abnormal "++show (ev_mode e) ++ " vs " ++ show (ev_mode e `mod` 16)) mode must be abnormal 17179869184 vs 0 mode must be abnormal 8589934593 vs 1 Now according to the docs, ev_mode should be a small integer. I suspect that we're seeing here an Int vs CInt issue. :( I've glanced at the code, but really have no idea how to read a .hsc file. In the meantime, we can work around the bug by using the above `mod` in our crossing check. I'll send a patch shortly (although you're welcome to replace it with a real fix, but since the x11 package is included in ghc's distribution, I think some sort of workaround is in order). -- David Roundy Department of Physics Oregon State University