[1707] Can not access env variables from plugin

I set in nuxt.config.js env variables

env: {
    language: process.env.NODE_LOCALE
  },

and after, when plugin code runs in server I get undefined.

import Vue from 'vue'
import VueI18n from 'vue-i18n'
Vue.use(VueI18n)
export default ({ app, isServer, env }) => {
app.i18n = new VueI18n({
    locale: env.language || 'en', #env.language === undefined
    fallbackLocale: env.language || 'en',
    messages: {
      'en': require('~/locales/en.json'),
      'es': require('~/locales/es.json'),
      'fr': require('~/locales/fr.json'),
      'de': require('~/locales/de.json')
    }
  })

I read doc several times but I can't find a solution.

Edit(more info): On my laptop(mac) works fine in dev and production mode, but in ubuntu 14.04 server is where stops working.

Edit2: I found my mistake, I wasn't exporting correctly variables before build. Please close the issue and sorry for the inconvenience.