<ul class="tabnav el">
    <li<?php if ($_SERVER['SCRIPT_NAME'] == '/shop/admin/customfields/manage.customfields.php' || ($_SERVER['SCRIPT_NAME'] == '/shop/admin/customfields/edit.customfield.php' && isset($_REQUEST['id']))) { ?> class="selected"<?php } ?>><a href="/shop/admin/customfields/manage.customfields.php">Manage</a></li>
    <li<?php if ($_SERVER['REQUEST_URI'] == '/shop/admin/customfields/edit.customfield.php' && !isset($_REQUEST['id'])) { ?> class="selected"<?php } ?>><a href="/shop/admin/customfields/edit.customfield.php">Add</a></li>
</ul>
