one-to-one constrained=false: can be loaded on demand? can be proxied?

Hi

In file org.hibernate.cfg.HbmBinder I can see the following comment:
else if ( "one-to-one".equals( node.getName() ) ) {
//NOTE SPECIAL CASE:
// one-to-one constrained=false cannot be proxied,
// so default to join and non-lazy
lazy = ( (OneToOne) model ).isConstrained();
fetchStyle = lazy ? FetchMode.DEFAULT : FetchMode.JOIN;
}
else {

Is this comment is still valid?
In other words: is it possible to "load on demand" (lazy loading) of a property mapped as:
one-to-one constrained=false
?

Regards, Adam Woźniak