Bas writes: "This is the first MARC4J [1] release and it includes a lot of new features, including support for LC's MARC XML [2]. Currently it's the only released tool that supports this new format. The MARC4J project is a continuation of James (Java Marc Events)." [note: the last James release was beta 5.]
Links:
[1] http://marc4j.tigris.org
[2] http://www.loc.gov/standards/marcxml/