gnome logout problem

[Manolis Kiagias]

I am really confused about this one, and don't know where to start.
I have gnome 2.18.3 compiled from ports (also gnome power tools and
gnome fifth toe)
Today, for the first time I used the lock screen option in the System
menu to leave my desktop unattended for a few minutes.
I then entered my password, and it would not accept it! This was not a
problem with caps lock or alternate keyboard layout (tried it several
times). I had to kill the X server with CTRL+ALT+BACKSPACE

Restarting with startx from the command line as usual, now I have a
problem with the logout option. Simply selecting logout from the menu
shows the usual dialog (switch user, cancel, logout) but pressing the
logout button, it remains recessed and nothing happens. If I wait long
enough (maybe about a minute) it finally logs me off.
The console messages just after the timeout occurs:

Window manager warning: CurrentTime used to choose focus window; focus
window may not be correct.
Window manager warning: Got a request to focus the no_focus_window with
a timestamp of 0.  This shouldn't happen!

What could possibly happen? I tried on another user account, same
problem. Any ideas?