Typo error

[cwchong]

approx line 560:

    $classes=ClassInfo::ancestry($className, true);
    foreach($classes as $class) {
        $db = Config::inst()->get($className, "db", CONFIG::UNINHERITED); // <-------
        if(!empty($db) && array_key_exists($sortColumn, $db)) {
            $table=$class;
            break;
        }
    }

the variable in the highlighted line should be $class instead of $className: $db = Config::inst()->get($class, "db", CONFIG::UNINHERITED);

[UndefinedOffset]

fixed good catch :)