XMLPersistence 1.0 is now available (1.1alpha also available in CVS).
http://xml-persistence.net/
XML Persistence is an opensource (BSD License) java transactional XML DOM persistence (PDOM) library. Using W3C DOM java API, developpers can store partial or complete document in database.
XML Persistence relies on
Hibernate library. Hibernate provides mapping beetween DOM and relationnal database and transactionnal operation on part of the documents.
By the way,
Hibernate offers good read/update/delete performances for such mapping appoach, and allows reliable application developpement.
XML Peristence has been successfully tested with HSQLDB and PostgreSQL database.