function showComments() {
    var $j = jQuery.noConflict();
    document.getElementById('commentstab').style.backgroundPosition= "bottom left";
    document.getElementById('pingstab').style.backgroundPosition= "top left";
    $j('#pings_section').fadeOut(500);
    $j('#comments_section').fadeIn(500);
}

function showTrackbacks() {
    var $j = jQuery.noConflict();
    document.getElementById('commentstab').style.backgroundPosition= "top left";
    document.getElementById('pingstab').style.backgroundPosition= "bottom left";
    $j('#comments_section').fadeOut(500);
    $j('#pings_section').fadeIn(500);
}