One of the 4 Adapters for Zend_Paginator is DbSelect which uses a Zend_Db_Select instance. Now, the problem occurred if I need to have some calculative data from other tables and use join with the Zend_Db_Select object for them.

He gives an example of a join that he performed with the component, the details of the "behind the scenes" code and why it happened that way. He also offers a solution (before the Zend_Pagination component was patched for it, of course) of changing the count() method it uses slightly to remove an unneeded part of the query.