I am happy to announce that we are expanding MOXy's XPath based mapping in EclipseLink 2.3. You are now able to map to an element based on the value of an attribute. This is done by leveraging XPath predicates via MOXy's @XmlPath annotation.
You can try this out today by downloading one EclipseLink 2.3.0 nightly downloads starting on March 22, 2011 from:
