Yeah, I just came from that page. I'm trying to find something that explicitly explains what the VSS database format is.

Using a relational database engine in a Java application requires that you map your application’s object model to fields within database tables. An order-entry application, for example, will consist ...

XML-DBMS provides modules for Java and Perl, but is not designed for standalone use. The main mapping object can be generated from a DTD or XSchema (the new XML schema format proposed by the W3C).