have you configured the JSF version correctly. JBoss comes with JSF 2 as default and you need to change to JSF 1.X instead.
Yes i changed this in web.xml as follows
I know there are different compatibility issues, but I don't know what components hey refer to in the context of Seam 2.
There are numerous threeds where they riase this issue, but until now they are not satisfactory answered by RedHat.
I would strongly advice to stick with jboss 5 with seam 2.