Ajuda com DELETE_ORPHAN no HIBERNATE

@Entity
@Table(name = "TB_FUNCIONARIO")
public class Funcionario extends PessoaFisica {

	/** serialversionUID **/
	private static final long serialVersionUID = 1350744945734500949L;

	/** lista de idiomas do funcionário **/	
	@ManyToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
	@JoinTable(name = "TB_FUNCIONARIO_IDIOMA", joinColumns = @JoinColumn(name = "ID_PESSOA", referencedColumnName = "ID_PESSOA"), inverseJoinColumns = @JoinColumn(name = "ID_IDIOMA", referencedColumnName = "ID_IDIOMA"), uniqueConstraints = @UniqueConstraint(columnNames = {
			"ID_PESSOA", "ID_IDIOMA" }))
	@Cascade(org.hibernate.annotations.CascadeType.DELETE_ORPHAN)
	private List<Idioma> idiomas;

@Entity
@Table(name = "TB_IDIOMA")
@TableGenerator(name = "idGenerator", table = "TB_SEQUENCE", allocationSize = 1, pkColumnName = "SEQ_NAME", valueColumnName = "SEQ_COUNT", pkColumnValue = "SEQ_IDIOMA")
public class Idioma extends EntityObject {

	/** serialversionUID **/
	private static final long serialVersionUID = -4488811991972462034L;

	/** identificador **/
	@Id
	@GeneratedValue(strategy = GenerationType.TABLE, generator = "idGenerator")
	@Column(name = "ID_IDIOMA", length = 10, precision = 0, insertable = true, updatable = false)
	private Long id;

	/** descrição do idioma **/
	@Column(name = "DS_IDIOMA", length = 120, precision = 0, insertable = true, updatable = true)
	private String idioma;