Catalyst and Maypole are tied to Appache web server. They are good for MVC work.
In fact ejb-app-servers may use MVC frameworks as a front-end, but one of ideas behind it is to split two tier application (web<->db) to three tier! (web<->app<->db)..In fact they can act as two tier too..
What I want to say is that MVC is a part of the whole picture.. and also that app-server is not tied to just web-model, it also can be used as a normal client-server app.. i.e u can access this app-server not only with web browser, but with Desktop app.