$(function() {
// opacity set
$(".g").css("opacity","0.4");

// on mouse over
$(".g").hover(function () {

// set opacity to 100
$(this).stop().animate({
opacity: 1.0
}, "slow");
},

// on mouse out
function () {

// set opacity back
$(this).stop().animate({
opacity: 0.4
}, "fast");
});
});