Still having problems with the screensaver in Knoppix? Here's another workaround. Install the xscreensaver package from Debian.org. Then open the “Control Center” in KDE. Select the “Appearance and Themes / Screensaver'' page. Turn off the “Enable Screensaver'' checkbox. Next, find the Autostart directory (/home/user/.kde/Autostart). Create a file in your Autostart directory called “xscreensaver.desktop” that contains the following five lines:

[Desktop Entry]
Exec=xscreensaver
Name=XScreensaver
Type=Application
X-KDE-StartupNotify=false

Now, when you next boot, xscreensaver will be your default screensaver application. The easiest way to configure xscreensaver after this is to simply run the xscreensaver-demo program (type “xscreensaver-demo” in the terminal – don't leave a space) and change the settings through the GUI. For more info you can visit http://www.jwz.org/xscreensaver/faq.html#xdm.