index.php :

Case 51 : # SITEMAP
if ($zc['sitemap']) {
$output = zina_cache('sitemap', 'zina_content_sitemap', null, ($zc['sitemap'] == 2));

The null argument gives the error : call_user_func_array() expects parameter 2 to be array, null given
in the function zina_cache() on line $output = call_user_func_array($func, $args);.

Changing the null to "array()" sort of fixes this.