Issue with Set collections with Javafx

[Daniele Renda]

Hi,
in my small application I've a pojo with a collection (Set).

public class MyBean{
    @OneToMany(fetch = FetchType.LAZY, orphanRemoval = true, mappedBy = "collectionSet", cascade = CascadeType.ALL)
    private Set<MyBean2> collectionSet;
}
public class MyBean2{
   private String property1;
   private String property2;  
   @ManyToOne(fetch = FetchType.LAZY, optional = false)
   private MyBean bean;
}

In the server I've a custom repository with a method that load my collection because it is LAZY:

@Override
    public Set<MyBean> loadCollection(Long id) throws Exception {
        MyBean bean= manager.find(MyBean.class, id);
        if (bean!= null) {
            bean.getCollectionSet.size();
            return bean.getCollectionSet();
        } else {          
            throw new Exception("Bean not found");
        }
    }

but in the JavaFx client when I call the method of repository I've this error:

Exception in runnable
java.lang.ClassCastException: flex.messaging.io.ArrayCollection cannot be cast to java.util.Set
    at it.pianetatecno.aci.client.ui.vendite.RiepilogoVenditaUi$3.result(RiepilogoVenditaUi.java:188)
    at org.granite.client.tide.impl.ResultHandler.run(ResultHandler.java:96)
    at com.sun.javafx.application.PlatformImpl$4.run(PlatformImpl.java:173)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.access$100(WinApplication.java:29)
    at com.sun.glass.ui.win.WinApplication$3$1.run(WinApplication.java:73)
    at java.lang.Thread.run(Thread.java:722)

Maybe it's a bug?

Thanks