I found the solution for my problem from last Friday. I simply had to remove the JSF API classes (WEB-INF/lib/jsf-api.jar) out of the war file. Then that application will work in a JBoss + JBoss Portal bundle. Apparently, the Portal adds those javax.faces.* packages somewhere very global?

Next step, try a Creator Portlet on the JBoss Portal;-)

Have fun,
— Marco