function change_preview(id)
{
    var text_box = document.getElementById('serendipity[template][' + id + ']');
    var image_box = document.getElementById(id + '_preview'); 
    var filename = text_box.value;
    image_box.style.backgroundImage = 'url(' + filename + ')';
    image_box.style.backgroundRepeat = 'no-repeat';
}
function choose_media(id)
{
    window.open('serendipity_admin_image_selector.php?serendipity[htmltarget]=' + id + '&serendipity[filename_only]=true', 'ImageSel', 'width=800,height=600,toolbar=no,scrollbars=1,scrollbars,resize=1,resizable=1');
}