$.tools.addTipEffect("slidedown",
    function() {  
        var opacity = this.getConf().opacity; 
        this.getTip().css({opacity:0}).animate({top: '+=15', opacity:opacity }, 300).show(); 
    },
    function() { 
        this.getTip().animate({top: '+=15', opacity:0  }, 10, function() {  
                $(this).hide().animate({top: '+=30'}, 0); 
        }); 
    } 
);