PNG backgrounds disappear in IE when using Jquery slides and fades

Question

I've got a simple Jquery script to slide part of my header, however in IE, when I process the slide and fades, all PNG backgrounds (they are set in CSS) disappear.

Please note that this script has been written inside of PHP hence all the slashes and marks :).

    <script type=\"text/javascript\">

$(document).ready(function(){
            $('#togHide').click(function(){
                $('#headhideL').slideUp('slow');
                $('#headhideR').slideUp('slow');
                $('#togHide').fadeOut('slow');
                $('#togShow').slideDown('slow');
                $('#headSearch_results').slideUp('slow');
                    $.ajax({
                        type: \"POST\",
                        url: \"functions/headerSES.php\",
                        data: \"sesDecide=hide\"
                    })
            }); 
            $('#togShow').click(function(){
                $('#headhideL').slideDown('slow');
                $('#headhideR').slideDown('slow');
                $('#togHide').fadeIn('slow');
                $('#togShow').slideUp('slow');
        if(document.getElementById('headSearch').value!='Search...' && document.getElementById('headSearch').value!=''){
                $('#headSearch_results').slideDown('slow');
        }
                    $.ajax({
                        type: \"POST\",
                        url: \"functions/headerSES.php\",
                        data: \"sesDecide=show\"
                    })
            });           
});
</script>

Any ideas would be greatly appreciated, unfortunately I only know half of Jquery.

Cheers :)