url "vrmlscript:
          function initialize()
          {
              // tell what events
              oldMask = Browser.eventMask;
              //Browser.eventMask = 1<<5; // KeyDown Only...
              Browser.eventMask = ((1<<5) | (1<<6)); // KeyDown and KeyUp
              // add event observer
              Browser.addRoute(Browser,'event_changed',me,'onEvent');
          }
          function shutdown()
          {
              // remove event observer
              Browser.eventMask = oldMask;
              Browser.deleteRoute(Browser,'event_changed',me,'onEvent');
          }