[xmonad] Focus getting stuck on one window

[Ben Butler-Cole]

Hello XMonad

I'm experiencing a sporadic problem with XMonad.

Sometimes when I start a session, I am unable to move focus away from
the first window that I open. I can launch further windows, but they
do not get focus. I can send the focused window to a different
workspace, in which case focus switches to another window (but I can't
then switch focus away from that window). When I try to switch focus
there is some flickering -- I think the red border disappears and then
reappears again as though focus very briefly switches where I'm trying
to send it and then goes back again.

I haven't been able to see any pattern in when this does and doesn't
happen. When it happens it starts immediately at the beginning of the
session. Restarting XMonad doesn't fix the problem; nor does logging
out and in again (I guess this is a big clue that there's something
pretty fundamentally wrong). On restarting my box I seem to get a
50/50 chance that it will happen.

I'm running Ubuntu 10.04, using XMonad from the standard package repo.

I'm conscious that this is a rather unhelpful bug report. Can you give
me any clues what I can do to get some more diagnostics for the
problem when I experience it?

Thanks
-Ben