Digester digester = new Digester();
digester.setNamespaceAware( true );
PluginRules rc = new PluginRules();
digester.setRules( rc );
PluginDeclarationRule pdr = new PluginDeclarationRule();
digester.addRule( "root/plugin", pdr );
// for plugins at pattern "root/widget", use xml attributes "id" and
// "class" in the custom namespace as the values for plugin id and
// class, not the default (and non-namespaced) values of