9.0.5.1: Puzzled by classes in client packages

Question

Currently we're using 9.0.3.3.
We started to look into 9.0.5.1. Now, when the migration is done, there are lots of new client packages containing ...Client and ...RowClient classes.
This is completely new to us. And we have problems with these classes too.
We use our own ViewObjectImpl/ViewRowImpl classes and have our own interfaces extending ViewObject and Row.
When my VO interface extends our own Row interface instead of oracle.jbo.Row then I cannot compile since methods are missing in the ...Client classes. I have to move every single method manually to the right in the wizard. I cannot shuttle the whole interface, since then the methods in oracle.jbo.ViewObject are also created in the ...Client class but some of those methods are final in oracle.jbo.client.remote.ViewUsageImpl (like isInternal()).
Another example:
An abstract VO of ours implements VieObject and a custom interface we defined. These methods are missing in the ...Client class too. And I cannot shuttle those methods to the right in the wizard, because they don't show up. And I cannot shuttle the interface in "Interfaces" because it doesn't show up either.
So what's the deal with the classes in client? Could someone please elaborate?
Do I really need those if I run in local mode? Why is it that my custom interface doesn't show up? I don't get it.
Thanks in advance,
Sascha

Answer 1

I have 9.0.5.2 up and running and created the classes exactly like I think you have said in 9.0.3. I took the liberty of assuming that the purpose of IFormContext was to return a FormContext object.
package test;
import java.io.Serializable;
public class FormContext implements Serializable {
  public FormContext() {}
package test;
import oracle.jbo.ViewObject;
public interface BaseViewObject extends ViewObject  {
  public void baseVOMethod();
package test;
import oracle.jbo.server.ViewObjectImpl;
public class BaseViewObjectImpl extends ViewObjectImpl  {
public void baseVOMethod() { }
package test;
public interface FormContextView extends BaseViewObject  {
public void   formContextMethod();
package test;
public class FormContextViewImpl extends BaseViewObjectImpl implements FormContextView, IFormContext {
  public void   formContextMethod() { }
  public FormContext getFormContext() {
     return null;
package test;
public interface IFormContext  {
    FormContext getFormContext();
}Then, I created a DeptView and set FormContextViewImpl as its Object class and (OK)'d the wizard.
When I go back into the wizard, I see:
test.FormContextView
test.IFormContext
in the list of Available interfaces.