function setmenu(){
	var menu_data;
	new Ajax.Request("./backend/menu.json", {method:'get', onComplete:assign_data});
	
	function assign_data(q){
		menu_data = q.responseText.evalJSON();
		assign_event_handlers();
		adjust_detail();
	}
	
	function assign_event_handlers(){
		for(var parent in menu_data){
			_assign_events(parent, menu_data[parent][1]);
			for(var child in menu_data[parent]["child"]){
				_assign_events(child, menu_data[parent]["child"][child][1]);
			}
		}
	};
	
	function _assign_events(elem, num){
		if (undefined == $('i_'+elem)){
			return;
		}
		var base_src;
		var over_src = "./image/global-over_"+num+".png";
		_preload_image(over_src);
		$('i_'+elem).observe('mouseover', function(event){
			var elem = event.element();
			base_src = elem.src;
			elem.src = over_src;
		});
		_preload_image(base_src);
		$('i_'+elem).observe('mouseout', function(event){
			var elem = event.element();
			elem.src = base_src;
		});
	}
	
	function _preload_image(src){
		var img = new Image();
		img.src = src;
	}
	
	function adjust_detail(){
		$("m_index").style.position = "absolute";
		$("m_index").style.left = "870px";
	}
}