DB_DataObject_FormBuilder : $fb_linkDisplayFields in inherited classes

Hello, The situation : - the main table DOCUMENTS - the secondary tables : LANGUAGES and CATEGORY There is a m:n relation between : - DOCUMENTS and LANGUAGES and between - DOCUMENTS and CATEGORY In the DOCUMENTS form, I can easily display checkboxes for the LANGUAGES and CATEGORY values (with "$fb_crossLinks"). The values displayed for the checkboxes are LANGUAGES and CATEGORY IDs. I would like to display the associated values. I know that I can do that by setting the "var $fb_linkDisplayFields = array('name');" in the auto-generated LANGUAGES and CATEGORY DataObject classes. My problem is that I don't want to modify those classes because they are auto-generated. If I alter the DB, then regenerate the DO, my modifications will be lost... So, I always work in classes that inherit from those auto-generated classes. But how can I do to specify "var $fb_linkDisplayFields = array('name');" in those inherited classes in place of the auto-generated ones. Thanks in advance for your help. Thomas Balthazar.