When:
- invoking JAXBContext.newInstance(String, ClassLoader)
- and when JAXB implementation is loaded through deprecated loading mechanism
- and when its creaeCotenxt method throws JAXBException instance
it's wrapped into another JAXBException which contradict the latest spec (not yet promoted):

    All RuntimeExceptions and JAXBExceptions thrown from provider's call are re-thrown, other exceptions are wrapped into an instance of JAXBException.

spec: http://cr.openjdk.java.net/~mkos/8138699/specdiff.04/javax/xml/bind/JAXBContext.html

The minimized testcase is attached.