function showHide(obj, status) {
	var subMenu = obj.getElementsByTagName("ul");
	if (subMenu.length > 0) {
		subMenu[0].style.position = "absolute";
		subMenu[0].style.display = status;
	}
}

function show_sub() {
	showHide(this, "block");
}

function hide_sub() {
	showHide(this, "none");
}


window.onload = function() {
	if (!document.getElementsByTagName) return false;
	if (!document.getElementById) return false;

	// enable drop-down menus

	if (!document.getElementById("mainnav")) return false;
	var mainMenu = document.getElementById("mainnav").getElementsByTagName("ul")[0];
	var subMenus = mainMenu.getElementsByTagName("ul");
	for (i = 0; i < subMenus.length; i++) {
			subMenus[i].style.display = "none";
	}
	var menuItems = mainMenu.getElementsByTagName("li");
	for (i = 0; i < menuItems.length; i++) {
		menuItems[i].style.position = "relative";
		menuItems[i].onmouseover = show_sub;
		menuItems[i].onmouseout = hide_sub;
	}

	// create pop-ups for appropriate links

	if (!document.getElementById("content")) return false;
	links = document.getElementById("content").getElementsByTagName("a");
	for (i in links) {
		aClass = "";
		if (links[i].className) aClass = links[i].className;
		if (aClass.indexOf("popup") >= 0) {
			links[i].onclick = function() {
				srcAttr = this.getAttribute("href");
				popup = window.open(srcAttr, "popup", "height=450,width=700,scrollbars=yes");
				return false;
			}
		}
	}
	
}