I just went to http://hibernate.org/orm/documentation/ and clicked on "Developer's guide", which points to 4.2 But it's also there if you change the version in the link: http://docs.jboss.org/hibernate/orm/4.3/devguide/en-US/html/ch15.html

I'll take a shot at creating the page, maybe sometimes next week (though I'm at conferences, who knows how it will turn out time-wise).