xfwm4: how to kill apps _safely_

[Jan Eidtmann]

hello xfce developers,
i'm still missing a kill option in xfwm4 like right-click on close kills
the app. i don't like using xkill or a terminal to kill the app, so here
comes a safer approach (it's not my idea, it's how gnome 2.10
(metacity(?)) handles it):

when the application does not respond to the close command, an dialog
box is telling you that the application doesn't respond and asks you if
you wanna kill the app or not. this happens after a timeout of 3 or 4
seconds after the user clicked the close button and the app did not
close.
i think that shouldn't be hard to implement nor will it add bloat to
xfwm4. it would just be a great plus for the useability of xfce4. imo.

what do you think about this?
cheers, cmak :)