if (!initialized) {
initialized = true;
// Initialise a content handler for the MCSI namespace.
NamespaceSwitchContentHandlerMap.getInstance().addContentHandler(
MCSI_URI, new MCSIContentHandlerFactory());
// Initialise MCSI expression facilities
ExpressionSupport.registerExternalNameSpacePrefix("mcsi", MCSI_URI);
ExpressionSupport.registerExternalFunction(
new ImmutableExpandedName(MCSI_URI, "policy"),