Comment 3 for bug 656847

HibernateDomainExporter provides now the functionality you requested :

        File configuration = new File("examples.hbm.xml");
        HibernateDomainExporter exporter = new HibernateDomainExporter(
          "Q", // name prefix
          new File("target/gen3"), // target folder
          configuration); // hbm files (varargs)

          exporter.export();