1. Jboss PortletBridge is JSR-301 implementation, that has additional features that let RichFaces and Jboss Seam to work in the portal environment. Because it uses standard specifications only, it should working properly in any JSR-286 compatible portals. Actually, it has been tested with Liferay, WebLogic, WebSphere while Jboss portal and GateIn its primary runtame environment.
2. I've never used RichFaces with Spring Portlet MVC. The com.sun.faces.portlet.FacesPortlet is pretty outdated class, that has been replaced by JSR-301 speck far ago, so I doubt that it would work fine with RichFaces.
On the other hand, Jboss PortletBridge has modular structure that allows to register custom 'Strategy' object to integrate with particular library, so it would be possible to create custom strategy for Spring Portlet MVC. That is not a trivial task that requires Portlet, JSF, and Spring expierence . I'm familiar with formers, but does not good enough with Spring Portlet to integrate bridge with it.
If you want, I can help you to create such integration module. Unfortunately, I have no time to do it on my own, except if such task will come from Red Hat commercial support, so I would reorganize priorities in official way.
Did you find a solution for this problem? I have the same one...