There's a need to be able to use the same criteria 2 times
i'm not able to do something like without the need to use a xfcp class adding e.g.
if (!empty($conditions['last_post_date2']) && is_array($conditions['last_post_date2']))
WHERE thread.last_post_date>= " . $foo AND thread.last_post_date<= " . $foo2
if this would be possible, lazy coders wouldn't need to create own methods and own queries for the getXXXByIdRange methods