Sun javac won't compile generated sources while OpenJDK does?

I use JPA and hibernate-jpamodelgen entities to generate sources for classes like EntityName_.java.

It's strange when I run javac from the Sun JDK (1.6.0_24), the sources for EntityName_are created but not compiled.

When I run OpenJDK one (1.6.0_22), it is generated and compiled. I can find the EntityName_.classfiles in the output directory.

Why is the difference? And can I somehow make Sun javac not only generate the source code, but also compile all the generated files?