The thing is, ICEfaces 2.0 is basically re-using the components from ICEfaces 1.8 (Which is why you're using the same namespaces at the top of your XHTML file.) Unfortunately, it does mean that you have to specifically tell your application to use those older components.
Add these lines to your web.xml:
And make sure you're importing the icefaces-compat.jar into your app.
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