function log() {
    if (!$.fn.ajaxSubmit.debug)
        return;
    var msg = '[jquery.form] ' + Array.prototype.join.call(arguments,'');
    if (window.console && window.console.log) {
        window.console.log(msg);
    }
    else if (window.opera && window.opera.postError) {
        window.opera.postError(msg);
    }
}
Checks/unchecks any matching checkboxes or radio buttons and
selects/deselects and matching option elements.