This does not seem to be fixed (Hibernate ORM SNAPSHOT hibernate-core-4.1.11-20130305.133113-3.jar). The index column is added in neither of scenario's below

parent.getChildren().add(parent);
mgr.save(parent);

or

mgr.save(child);

public class Parent{
@OneToMany(cascade={ CascadeType.ALL },orphanRemoval=false,mappedBy="parent",fetch=FetchType.LAZY)
@LazyCollection(LazyCollectionOption.EXTRA)
@OrderColumn(name="idx")
public List<Child> getChildren()

[...]
public class Child{
//no index attribute
@ManyToOne(fetch=FetchType.LAZY,optional=true)
@JoinColumn(name="FK_ParentId",nullable=true, insertable=false,updatable=false)
public Parent getParent() {
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