Please have a look at the documentation on JBossWS - Apache CXF integration on JBoss AS 7 : https://docs.jboss.org/author/display/AS71/Webservices+reference+guide
In particularm you're not expected to have that web.xml referring cxf servlet.
There're some examples you can have a look at in the jbossws source distributions at http://www.jboss.org/jbossws/downloads