Rails dataTable internationalization

I am looking to display datatable with the fields shown in the current local, instead of english. I saw on the datatables.net that I should just add languages before the options, but when I do so, the options totally disapears and the table shows as plain, without the search, entries, etc.

I did the following in my xxx.coffee:

  $("#table_cadeau").dataTable({
    "language": {
      "searching": true
      "limit": 5
      "lengthMenu": [[5,10,25,50, 100,250,-1],[5,10,25,50, 100,250,"All"]]

    }})

Does anyone knows what should be added or modified please ? Thanks!