Hi,
another alternative is JaxMe (
http://jaxme.sf.net). JaxMe 1 is very
close to JAXB in the runtime (it already has a JAXBContext and most
of the marshaller and unmarshaller methods) and includes a persistence
layer with relational and/or native XML databases as the backend.
JaxMe 2 aims to be a JAXB implementation and is close to the first
alpha release. However, the persistence layer for that version will
need some more time.
Jochen