JpaContainer: how can I change the column headers of the OneToMany attribu

Flow
1

I have an entity like this
@Entity
public class Oferta {
//private static final long serialVersionUID = 1L;

 @Id
 private String id;
 private String titulo;     
 private String descrip;

 // more simple attributes .........

 //bi-directional many-to-one association to EtiquetaOferta
 @OneToMany(mappedBy="oferta")
 private List<EtiquetaOferta> etiquetaOfertas;

I created a proyect using maven JpaContainer artifact , it generates CRUD using FieldFactory, and display a table with DB_table data, when I select a row in the upper table its display a form with the simple attributes (id,titulo, descrip) and the OneToMany attribute etiquetaOfertas with a table

how can I change the column headers of the OneToMany attribute etiquetaOfertas?

is a masterDetailEditor ?

how I get a reference to it ?

thanks