Nullable many-to-one relationship

[ramon.turnes]

I have started to play a little bit with ROO in order to evaluate it for a future project. I have come across one problem which I don't know how to go around it. I have an entity that has a reference to its parent unless the entity is a root entity, that is, the entity has children but no parent. I have modelled it in the following manner:

@RooJavaBean
@RooToString
@RooJpaActiveRecord
public class LogicalReportGroup {
@ManyToOne
private QosLogicalReportGroup parent;
}

The problem is that it seems that the GUI does not support nullable many-to-one relationships so as soon as
I add the first logical report group, this automatically becomes the parent of all new logical report groups. I guess the problem is that the select input field that is displayed for the parent relationship does not have a default null value.