When logging out metacity brings up a dialog with applications that did not react to the "save session" signal or something. The only option for the user is to "close" the dialog.

For me this happens always with xchat for example.

It is very annoying because it forces extra actions of the user to really logout/shutdown *without* offering an option to cancel the logout process. So after seeing this some times it just annoys the user by informing him, that some app could not save data but nothing can/will be done. He is trapped and that gives a generally bad feeling of "I know you will lose data but there is nothing you can do about it".

I suggest several possible ways to fix this:

1) remove the dialog completely because in that ways it does more harm than good.
2) add a "cancel logout" option to allow the user to shut the application(s) in question manually
3) add a "don't tell me next time" or "remember my decision" checkbox so that users get informed, that some apps could not save their session but are able to disable this dialog if they know there is no critical dataloss for the concerned apps (like with xchat).