code: public JSONObject getAccountInfoByEmail(String email)
        throws GitkitClientException, GitkitServerException {
      try {
        JSONObject params = new JSONObject()
            .put("email", new JSONArray().put(email));
        return invokeGoogle2LegOauthApi("getAccountInfo", params);
      } catch (JSONException e) {
        throw new GitkitServerException(e);
      }
    }
docs: Using 2-Leg Oauth (i.e. Service Account).