ben bu jquery oylama script, her şey iyi çalışıyor, sadece ajax isteği başarı işlevi de görüntü görüntü değiştirme olmadığını var?

jQuery:

$("a.vote_down").click(function(){
    //get the id
    the_id = $(this).attr('id');



    //the main ajax request
        $.ajax({
            type: "POST",
            data: "action=vote_down&id="+$(this).attr("id"),
            url: "votes.php",
            success: function(msg)
            {
                $("span#votes_count"+the_id).fadeOut();
                $("span#votes_count"+the_id).html(msg);
                $("span#votes_count"+the_id).fadeIn();
                            // this is my problem here
                $("span#vote_buttons"+the_id).attr("src", "images/downvoteActive.png");

            }
        });
    });

html:

<span class='vote_buttons' id='vote_buttons<?php echo $row['id']; ?>'>
        <a href='javascript:;' class='vote_up' id='<?php echo $row['id']; ?>'>Vote Up!</a>

        <a href='javascript:;' class='vote_down' id='<?php echo $row['id']; ?>'>Vote Down!</a>

css:

a.vote_up, a.vote_down {
    display:inline-block;
    background-repeat:none;
    background-position:center;
    height:16px;
    width:16px;
    margin-left:4px;
    text-indent:-900%;
}

a.vote_up {
    background:url("images/upvote.png");
}

a.vote_down {
    background:url("images/downvote.png");
}

        </span>