var help = function(link){
	this.link = link;
	//private methods
	initHelp = function(){
		var childs = link.parentNode.childNodes;
		for(var i = 0; i < childs.length; i++)
		{
			if(childs[i].className == "help"){
				return childs[i];
			}
		}
		return null;
	}
	var help = initHelp();
	//events
	link.onmouseover = function(){
		if(help!=null)show(help)
	}
	link.onmouseout = function(){
		if(help!=null)hide(help)
	}
}