Hibernate requires Java 7 to build. We do target Java 6 in compilation. We do, however, allow Java 7 features in tests.

The need for Java 7 to build is real. There is a bug in Oracle's JDK 6 javac which affects our codebase. They fixed it in JDK 7, but never backported it.

The website does not call out this fact, you are correct. It was, however, discussed on the developer mailing list if you are interested in the specifics.