Extensions to the G11NToolKit L10N project are loaded from specific packages. Each extension package must add an import element to this file to import the top level Ant file for the package. Each package must be unique and independent of any other extension package. The import element for a package must precede the import for the pkg.xml file. Other than that, ordering should not matter. Only one extension package may implement the copysrctar-ext, tok-ext, and detok-ext targets.