var the_delay = 2; // the close drop-down delay in seconds
var the_timeout;
// array of all dd menu ids. 'close_all' not allowed
nav_elements = new Array ('subONE','subTWO','subTHREE','subSIX');

function showHideNav (submenu_id){
  if (document.getElementById) {
    if (submenu_id) {
	  window.clearTimeout(the_timeout);
      for (var i = 0; i < nav_elements.length; i++) {
        if (nav_elements[i] == submenu_id) {
		  // if rollover do this
          document.getElementById(nav_elements[i]).style.visibility = 'visible';
	    }else{
		  // if rollout do this
          document.getElementById(nav_elements[i]).style.visibility = 'hidden';
		}
      }
    }else{
	  timer (the_delay);
	}
  }
}

function timer(delay){
  delay *= 1000;
  the_timeout = window.setTimeout("showHideNav('close_all')",delay);
}