var col = new Image(); 
col.src = '/templates/images/arrow_down.gif'; 
var exp = new Image();
exp.src = '/templates/images/arrow_top.gif';  

function toggle_ul(id)
{
	
	var ul_id = document.getElementById(id);
	if(ul_id.className=='open')
	{
		ul_id.className = "closed";
		//fetch_memory_handler(id,2);
		change_sign(id,exp.src);
	}
	else
	{
		ul_id.className = "open";
		//fetch_memory_handler(id,1);
		change_sign(id,col.src);
	}
	
	return false;
}

function change_sign(id,sign)
{
	document['s' + id].src = sign;
}