The K Desktop Environment

4.11. Whenever I start KDE, it complains about "shadow passwords". Why?

When your system uses shadow passwords, the screensaver can only run properly if the suid bit is set. This bit gives the screensavers root privileges, which are needed to access the shadow passwords. (Remember: the screensavers might be configured to secure the machine until the password is entered.)

To set the suid bit on the screensavers, you (or the systems administrator) must issue the following commands as root:

 chown root $KDEDIR/bin/*.kss
 chmod u+s $KDEDIR/bin/*.kss

Alternatively, if you compile KDE from source, you can use

 ./configure --with-shadow

to configure kdebase. Then the suid bit is set automatically during make install.