I haven't looked into the details of it, but a quick glance of that code you posted shows:
import javax.ejb.Stateless;
import javax.jws.WebService;
import org.jboss.wsf.spi.annotation.WebContext;
@Stateless
@WebService(name="GetBasisartikelService")
@WebContext(contextRoot="/jaxws-samples-retail")
public interface GetBasisartikelService
So you are marking an interface as a @Stateless? That's not allowed.