[wscompile] error: invalid remote interface

Question

I have an interface I want to publish as a web service. This interface extends java.rmi.Remote and each of its methods throws a RemoteException. But when I run wscompile (via ant) against this interface in order to have the wsdl file generated it gives me:
error: invalid remote interface; class manplan.j2ee.service.project.ProjectManager is not an interfacee
I have searched the forum and the internet yet could not find an answer. Any hints are most welcome. Below you will find excerpts from the relevant files.
Cheers,
Olaf
[interface]
public interface ProjectManager extends java.rmi.Remote
     void createProject(final Project project) throws DuplicateProjectException,
               ProjectManagementRuntimeException, RemoteException;
[ant]
<wscompile
     keep="true"
     define="true"
     base="${ws.build.classes.dir}"
     xPrintStackTrace="true"
     verbose="true"
     model="${ws.build.dir}/${ws.model.rpcenc.file}"
     config="${ws.conf.rpcenc.file}">
     <classpath>
          <path refid="ws.class.path"/>
     </classpath>
</wscompile>
[interface-config.xml]
<configuration
xmlns="http://java.sun.com/xml/ns/jax-rpc/ri/config">
<service
name="ProjectManagementService"
targetNamespace="urn:manplan:Services"
typeNamespace="urn:manplan:Types"
packageName="manplan.j2ee.webservice">
<interface name="manplan.j2ee.service.project.ProjectManager"/>
</service>
</configuration>

Answer 1

OK. Found it: unlike Axis' java2wsdl does wscompile not support JavaBeans and so it gets confused by all those Project params and return types. So I guess wscompile is not the right tool for me in this situation?
Cheers,
Olaf