Java 6 and JaxB 2.1

Question

The original release of Java 6 came with JAXB 2, but I have been told that 'later' Java 6 releases ship with JAXB 2.1.

Does anyone know what the first version of Java 6 to ship with JAXB 2.1 was?

Answer 1

Apparently Java 6 Update 4 was the first version to ship with JAXB 2.1 (source).