Are there role-based declarative authorization frameworks for rich browser-based web applications?

Before I say anything else: yes, I know that authorization has to be done on the server side. However, the client application must still hide the GUI elements that do not apply to the logged in user.

Having said that, the question here is: are there role-based declarative authorization frameworks for rich web applications for a browser-based browser?

Background: With browser based web applications (GWT, ExtJS, etc.), there is generally no need to create a dynamic view on the server side as the entire application can be loaded as static files and all view transitions are done in the browser Thus, implementing role-based security requires either dynamically configuring the GUI after the user logs in, or loading the application, or dynamically generating server-side application files after logging in, before anything is downloaded to the client (maybe built and cached too). This SO question discusses these approaches: How to use Ext JS for a role-based application

Thank!