I have the same issue but with vlc and on Squeeze (xdg-utils 1.0.2+cvs20100307-2) which has the same version of the xdg-screensaver script.
Strange thing is, after running 'gnome-screensaver --poke' once in the terminal while vlc is playing the movie seems to cause xdg-screensaver to work (meaning after a one-time gnome-screensaver --poke the screensaver doesn't kick in anymore). While running VLC, these *two* processes are running in the background: jochem@rock:~$ ps uaxw|grep xdg-screen jochem 3505 0.0 0.0 4000 336 ? S 22:00 0:00 /bin/sh /usr/bin/xdg-screensaver suspend 0x0120131c jochem 3514 0.0 0.0 4000 392 ? S 22:00 0:00 /bin/sh /usr/bin/xdg-screensaver suspend 0x0120131c -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]

