Well, turns out JSF 2.0 offer a nice support for JSR 3.0 :)
I simply removed the jsf-facelet.jar from my classpath and the FaceletViewHandler from my faces-config.xml. Those aren't needed anymore with JSF2.0.
Turns out I don't even the need the "validateBean" tag, has the validation is done automatically on the JSR-303 annoted fields. Impresive!
However, for some reasons my JSTL is not working anymore, but I guess this must be a common issue.
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