Facebook "locale" attribute not given by Graph API

i'm trying to extract an user locale from Facebook via Facebook Graph Api.

http://ift.tt/1EcMoI6

For example, this URL request returns me a locale:

{
   "id": "100000879345465",
   "first_name": "Marcus",
   "gender": "male",
   "last_name": "Maia",
   "link": "http://ift.tt/1F1SkB4",
   "locale": "pt_BR",
   "name": "Marcus Maia",
   "username": "marcusmaiaa"
}

But... when i try do to this same request via Facebook Graph API (using the Graph API Explorer with an app access token), it doesn't give me a locale:

{
  "id": "100000879345465", 
  "first_name": "Marcus", 
  "last_name": "Maia", 
  "link": "http://ift.tt/1EcMoYo", 
  "name": "Marcus Maia", 
  "updated_time": "2014-10-25T20:56:05+0000"
}

Why? I didn't found anything about it in the documentation.

Thanks