Laravel Elixir - run version task from extension

I'd like to make an extension for Laravel Elixir. In my own extension I need to run an existent Elixir version() task. How can I do this?

A bit of my code:

// File: elixir-extensions.js

var gulp   = require('gulp');
var Elixir = require('laravel-elixir');

var Task = Elixir.Task;

Elixir.extend('recursive', function(dir) {

    new Task('recursive', function(dir) {
        // Generate files list for versioning...
        var files = []; 

        // ...

        // Here I need to run Laravel Elixir version(files) with my files list

    });
});

via Chebli Mohamed