function highlightLines(id, lines, className) {
    if (typeof id == 'undefined' || typeof lines == 'undefined') {
        return;
    }
    if (typeof className == 'undefined') {
        className = 'highlighted';
    }
    var listItems = $(id).previous().down().next().childElements();
    listItems.each(function(listItem, index) {
        if (lines.indexOf(index + 1) != -1) {
            listItem.addClassName(className);
        }
    });
}