jQuery addClass for hover effect not working in Safari.

Question

This code works in FF 3.5.7 and ie7 and ie8. I'm just adding and removing a class which has a background image (a subtle off-white gradient) to change the background image on hover. Can anyone help me get this working in Safari? Thanks!

the example page is @ http://cambridgeuplighting.com/home (look in the footer in the three columns)

Btw in the code, the portion that is not working is .addClass('thirdHover') ... the ('span.icon') portion is working fine. Although it is definitely adding the class in FF and IE. Here is the Code:

jQuery(function( $ ){
    $('.oneThird').hover(function(){
        $(this).addClass('thirdHover');
        $(this).find('span.icon').css( {'background-position': '0px -60px'} );
    }, function(){
        $(this).find('span.icon').css( {'background-position': '0px 0px'} );
        $(this).removeClass('thirdHover');
    });
});