function AccordionList(_id, _callback) {
	var id = new Array();
	var callback;
	(!_isArray(_id))?id.push(_id):id=_id;
	(typeof _callback=="function")?callback=_callback:callback=function(){};
	
	for (var x=0;x<id.length;x++) {
		var dl = document.getElementById(id[x]);
		var dt = dl.getElementsByTagName("dt");
		for (var j=0; j < dt.length; j++) {
			var state = dt[j].getAttribute("class");
			// no classes defined, add class attribute with value 'collapsed'
			if (state == null) {
				dt[j].setAttribute("class", "collapsed");
				state = dt[j].getAttribute("class");
			}
			var expanded = state.search(/expanded/)+1;
			
			// find corresponding dd element
			var dd = dt[j];
			do dd = dd.nextSibling;
				while (dd && dd.nodeType != 1);
			(expanded)? dd.style['display'] = "block" : dd.style['display'] = "none" ;
			
			dt[j].onclick = function() {
				var dd = this;
				var state = this.getAttribute("class");
				var expanded = state.search(/expanded/)+1;
				var toggle;
				(expanded) ? toggle = state.replace(/expanded/, "collapsed") : toggle = state.replace(/collapsed/, "expanded") ;
				this.setAttribute("class", toggle);
				
				do dd = dd.nextSibling;
					while (dd && dd.nodeType != 1);
				(dd.style['display'] == "none")? dd.style['display'] = "block" : dd.style['display'] = "none" ;
				callback(this);
			}
		}	
	}
}

function _isArray(x){
	return ((typeof x == "object") && (x.constructor == Array));
}

function addEvent(_event, _function) {
	var _current_event = window[_event];
	if (typeof window[_event] != 'function') {
		window[_event] = _function;
	} else {
		window[_event] = function() {
			_current_event();
			_function();
		}
	}
}