findManyToManyRowset + condition

I'm writing here because I can't fix my problem

I want to list products in a specific category (with a IntersectionTableClass), and it's work:

    $products = 
                $category->findManyToManyRowset(
                    'App_Table_Eshop_Products',
                    'App_Table_Eshop_Products_Categories',
                    null,
                    null,
                    $categoryDB->select()->limit(App_Model_Eshop_Product::MAX_PRODUCTS_PER_PAGE, App_Model_Eshop_Product::MAX_PRODUCTS_PER_PAGE * ($page - 1))
                );

But i'd like to put a condition on my products (App_Table_Eshop_Products). I try to put this conditions in the 'Rules' but it's doesn't work.

thank you for your help

Geoffrey.

I'm so sorry about my englsih :(