Version: (using KDE 4.1.0) Installed from: Ubuntu Packages When the user configures the session manager to restore last session, it should automatically exclude any commands launched from autostart folders. Currently such commands end up getting launched twice unless the user specifically excludes them. Since session restoration is the default - many users will never even know they have that option, they will just realise that programs which autostart (and many apps set up autostart during install) are running more and more times - some users have ended up with 20 copies of the same program launching at startup.
You should report bugs to those applications - they should either autostart or use session management, but not mix both.