Comment 12 for bug 121737

Yes, and you can set whether or not it asks password on resume from suspend and hibernate in the xfce4-power-manager's preferences. But in Karmic, the log out dialog does not use a power manager to suspend and hibernate. In principle, a log out dialog is not the right place for suspend/hibernate, as those actions do not log out from the current session. (There are other ways to suspend and hibernate, such as using a power manager's tray applet.) If I remember right, an earlier release of Xubuntu had a patch by which a user was able to remove suspend and/or hibernate buttons from the dialog in settings. That said, I think it is good, if you can sometimes suspend/hibernate without locking: In some cases it saves time and reduces the risk of someone getting your password when you know you won't leave your computer.

See also http://bugzilla.xfce.org/show_bug.cgi?id=5853