One way is to expose the webservice using a wsdl first approach. To do this look at /examples/cxf-wsdl-first-osgi-package. Then in your cxf-se impl (i.e. the business logic) you invoke on the back ejb using rmi/iiop.
It may also be possible to do do the whole thing using a camel route which exposes the webservice using a cxf:endpoint and does the pass-thru to an rmi: endpoint.
Hope this helps
Do you have any suggestion where to find a tutorial or example that describe how to do this with camel?