@dai-kun - Did you delete this line in the hook?
Code:
$post_thanks_cashe = $db->query("SELECT " . TABLE_PREFIX . "post_thanks.* FROM " . TABLE_PREFIX . "post_thanks, " . TABLE_PREFIX . "post WHERE " . TABLE_PREFIX . "post.postid = " . TABLE_PREFIX . "post_thanks.postid AND " . TABLE_PREFIX . "post.threadid = '$post[threadid]' ORDER BY " . TABLE_PREFIX . "post_thanks.username ASC");
If you didn't, please do so. It's the main problem source.