There was some discussion about this already. We need to make sure that some vital apps (esp. a window manager) are running after startup. GNOME recently realized that they suffer from the same problem and came up with a D-BUS based solution, see John's blog: http://www.martianrock.com/?p=33 It'd be cool if we could be compatible with gnome-session there, to not reinvent the wheel.
Something for 4.6?
(In reply to comment #1) > Something for 4.6? > *bump*
Reassign to xfce-bugs@xfce.org.
*** Bug 8324 has been marked as a duplicate of this bug. ***
*** Bug 7324 has been marked as a duplicate of this bug. ***
Should be somewhat fixed since 4.14