diff --git a/scripts/xdg-screensaver.in b/scripts/xdg-screensaver.in
index 579b80e..84369cb 100644
--- a/scripts/xdg-screensaver.in
+++ b/scripts/xdg-screensaver.in
@@ -216,6 +216,13 @@ track_window()
   echo "$window_id:$xprop_pid" >> $tmpfile
   $MV "$tmpfile" "$screensaver_file"
   unlockfile
+  # in KDE4, simulating user activity prevents the screensaver autolock
+  if [ "$DE" = "kde" -a x"$KDE_SESSION_VERSION" = x"4" ]; then
+      while kill -0 $xprop_pid; do
+	  qdbus org.freedesktop.ScreenSaver /ScreenSaver SimulateUserActivity > /dev/null
+	  sleep 5
+      done
+  fi
   # Wait for xprop to edit, it means that the window disappeared
   wait $xprop_pid
   # Clean up the administration and resume the screensaver