Hello, I have the same problem, have you resolved it?
I'm afraid this is a bug in Richfaces 4.0 Final release. In fact there's no ArrangeableModel demo in richfaces-showcase 4.0 Final: the example you can see at http://showcase.richfaces.org/richfaces/component-sample.jsf?demo=dataTable&sample=arrangeableModel&skin=blueSky
is not included in the war file available at https://repository.jboss.org/nexus/content/groups/public/org/richfaces/examples/richfaces-showcase/4.0.0.Final/
Luckily, I've downloaded the 4.1 Final release and with these news libs my app uses ArrangeableModel filtering options without any problems.