In a normal use case, when you navigate away from a normal ICEfaces page, the client bridge attempts to dispose the views on that page along with any request-scoped beans that are associated with it. With portlets there can be 1 or more views that are registered and the dispose-views request will send all the views on that page.

However if you a number of portlets on the page and navigate away from the portal page before it's had a chance to render all the portlets, the views that have not yet been rendered (along with their request-scoped beans) will be orphaned. This is due to the fact that the server-side objects (views and request beans) are created for all the portlets but the ones that are not rendered don't get a chance to register themselves with the client bridge. This means that when the dispose-views is issued, it only includes the views that it knows about (ie the ones that have been rendered).