Does Emacs wm-window handling misbehave?

[Mathias Dahl]

Lately I am having problems switching windows (window manager windows)
using Alt+Tab. Like exactly right now when I type this in Emacs I try
to switch window and it does not work. I can see the frame of other
windows being marked/outlined and in the task bar the name of the
window I am trying to switch to becomes bold. I have to use the mouse
to switch instead, very annoying.

Until today I have thought this being a glitch in Metacity but by
chance I stumbled upon the following messages in my .xsession-errors
file today:

    Window manager warning: last_focus_time (5775062) is greater than
    comparison timestamp (3763886959).  This most likely represents a
    buggy client sending inaccurate timestamps in messages such as
    _NET_ACTIVE_WINDOW.  Trying to work around...

    Window manager warning: last_user_time (5775062) is greater than
    comparison timestamp (3763886959).  This most likely represents a
    buggy client sending inaccurate timestamps in messages such as
    _NET_ACTIVE_WINDOW.  Trying to work around...

    Window manager warning: 0x3c000a4 (.emacs) appears to be one of the
    offending windows with a timestamp of 5775062.  Working around...

It suddenly occurred to me that I only experience the switching
problem in Emacs and here is a reference to one of my Emacs
windows. Could it be a coincidence or is Emacs doing anything bad? I
don't want to report this as a bug just yet. Does anyone else have similar
experiences? I cannot say when it happens, it suddenly does. When I have
switched using the mouse it works again, for a while...

Some information:

In GNU Emacs 23.0.60.2 (i686-pc-linux-gnu, GTK+ Version 2.12.0)
 of 2008-03-13 on klibb
Windowing system distributor `The X.Org Foundation', version 11.0.10300000
configured using `configure  '--with-x-toolkit=gtk' '--with-gif=no'
'--with-dbus''

Ubuntu GNU/Linux 7.10 with latest patches.

/Mathias