Action shows form instead of a tree

Hi, i'm using OpenERP 7.0. I've extended res.partner model and I've created custom form and trees in my custom module for a res.partner model. I've created three actions and 1 menu. It works fine, the only thing that is not working is that when I click the menu, an empty forms is being showed, instead of the tree with Sociosres.partnerformtree,form[('apellido','<>',False)]Gestionar la base de socios, relaciones, asistencia a cursos y eventostreeform Is there something i'm doing wrong?