function getElementsByClass(searchClass,node,tag) {
	var classElements = new Array();
	if ( node == null )
		node = document;
	if ( tag == null )
		tag = '*';
	var els = node.getElementsByTagName(tag);
	var elsLen = els.length;
	var pattern = new RegExp("(^|\\s)"+searchClass+"(\\s|$)");
	for (i = 0, j = 0; i < elsLen; i++) {
		if ( pattern.test(els[i].className) ) {
			classElements[j] = els[i];
			j++;
		}
	}
	return classElements;
}

function attachNavEvents(){
	nav = getElementsByClass('nav');
	for(i=0;i<nav.length;i++){
		curr_nav = nav[i];
		if(curr_nav.getElementsByTagName('ul')[0]){
			//sub1 = curr_nav.getElementsByTagName('ul')[0];
			curr_nav.onmouseover = function(){
				this.getElementsByTagName('ul')[0].style.visibility = 'visible';
			}
			
			curr_nav.onmouseout = function(){
				this.getElementsByTagName('ul')[0].style.visibility = 'hidden';
			}
			nav_sub = curr_nav.getElementsByTagName('ul')[0].childNodes;
			for(s=0;s<nav_sub.length;s++){
				if(nav_sub[s].nodeType == 1){
					curr_sub = nav_sub[s];
					if(curr_sub.getElementsByTagName('ul')[0]){
						curr_sub.onmouseover = function(){
							this.getElementsByTagName('ul')[0].style.visibility = 'visible';
						}
						curr_sub.onmouseout = function(){
							this.getElementsByTagName('ul')[0].style.visibility = 'hidden';
						}
					}
				}
			}
		}
	}
}

window.onload = function(){
	attachNavEvents();
}