I am using a model object that implements the BeanModelTag interface ... However, if I have to define a cell renderer, it takes a model object that extends the BeanModel. Is my bean supposed to extend the BeanModel and implement the BeanModelTag interface too ? If I did that, I get a run time exception that there is no factory method for my model object. How do I use my existing bean that implements the bean model interface to define a cell renderer too ?