You need to add a dependency to org.apache.cxf module into your deployment's MANIFEST.MF, as explained above here.
The jbossws-cxf testsuite has many examples of direct cxf api usage, you can checkout http://anonsvn.jboss.org/repos/jbossws/stack/cxf/tags/jbossws-cxf-4.0.0.Beta2/ or http://anonsvn.jboss.org/repos/jbossws/stack/cxf/tags/jbossws-cxf-4.0.0.Beta3 , build and run the testsuite. See the documentation on how to build and run the testsuite.