How to switch user from screen-saver?

[Josef Wolf]

Hello,

On Karmic, the password dialog of the screen saver offers a button to
change user. Up to jaunty this used to start a second X session. But
on Karmic this fails and (after unlocking) an error is shown which tells
me

 The name of org.gnome.DisplayManager was not provided by any .service
 files

Any ideas?

BTW: in jaunty, the session indicator applet used to have options to change
user and to start a guest session. This functionality seems to be gone in
karmic. Any ideas what happened to it?