diff --git a/lib/Alchemy/Phrasea/Application/Api.php b/lib/Alchemy/Phrasea/Application/Api.php
index 50f90e612d..f2eb7888c1 100644
--- a/lib/Alchemy/Phrasea/Application/Api.php
+++ b/lib/Alchemy/Phrasea/Application/Api.php
@@ -27,7 +27,6 @@ use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 
 return call_user_func(function ($environment = PhraseaApplication::ENV_PROD) {
-
     $app = new PhraseaApplication($environment);
     $app->loadPlugins();
 
@@ -40,6 +39,7 @@ return call_user_func(function ($environment = PhraseaApplication::ENV_PROD) {
         return $monolog;
     }));
 
+    // handle API content negotiation
     $app->before(function(Request $request) use ($app) {
         // register custom API format
         $request->setFormat(\API_V1_result::FORMAT_JSON_EXTENDED, \API_V1_adapter::$extendedContentTypes['json']);
@@ -57,28 +57,30 @@ return call_user_func(function ($environment = PhraseaApplication::ENV_PROD) {
         if (null === $format) {
             $app->abort(406);
         }
-
-        // set request format according to negociated content or override format with jsonp is callback parameter is defined
-        if (trim($request->query->get('callback')) !== '') {
-            $request->setRequestFormat('jsonp');
+        // set request format according to negotiated content or override format with JSONP if callback parameter is defined
+        if (trim($request->get('callback')) !== '') {
+            $request->setRequestFormat(\API_V1_result::FORMAT_JSONP);
         } else {
             $request->setRequestFormat($request->getFormat($format->getValue()));
         }
 
         // tells whether asked format is extended or not
         $request->attributes->set('_extended', in_array(
-            $request->getRequestFormat('json'),
+            $request->getRequestFormat(\API_V1_result::FORMAT_JSON),
             array(
                 \API_V1_result::FORMAT_JSON_EXTENDED,
                 \API_V1_result::FORMAT_YAML_EXTENDED,
                 \API_V1_result::FORMAT_JSONP_EXTENDED
             )
         ));
-    });
+    }, PhraseaApplication::EARLY_EVENT);
 
     $app->after(function(Request $request, Response $response) use ($app) {
+        if ($request->getRequestFormat(\API_V1_result::FORMAT_JSON) === \API_V1_result::FORMAT_JSONP && !$response->isOk() && !$response->isServerError()) {
+            $response->setStatusCode(200);
+        }
         // set response content type
-        $response->headers->set('Content-Type', $request->getMimeType($request->getRequestFormat()));
+        $response->headers->set('Content-Type', $request->getMimeType($request->getRequestFormat(\API_V1_result::FORMAT_JSON)));
     });
 
     $app->register(new \API_V1_Timer());
diff --git a/lib/Alchemy/Phrasea/Core/Provider/ContentNegociationServiceProvider.php b/lib/Alchemy/Phrasea/Core/Provider/ContentNegociationServiceProvider.php
new file mode 100644
index 0000000000..3fe47266ce
--- /dev/null
+++ b/lib/Alchemy/Phrasea/Core/Provider/ContentNegociationServiceProvider.php
@@ -0,0 +1,37 @@
+<?php
+
+/*
+ * This file is part of Phraseanet
+ *
+ * (c) 2005-2014 Alchemy
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Alchemy\Phrasea\Core\Provider;
+
+use Silex\Application;
+use Silex\ServiceProviderInterface;
+
+class ContentNegociationServiceProvider implements ServiceProviderInterface
+{
+    public function register(Application $app)
+    {
+        $app['negociator'] = $app->share(function ($app) {
+            return new \Negotiation\Negotiator();
+        });
+
+        $app['format.negociator'] = $app->share(function ($app) {
+            return new \Negotiation\FormatNegotiator();
+        });
+
+        $app['langage.negociator'] = $app->share(function ($app) {
+            return new \Negotiation\LanguageNegotiator();
+        });
+    }
+
+    public function boot(Application $app)
+    {
+    }
+}
diff --git a/lib/classes/API/V1/result.php b/lib/classes/API/V1/result.php
index ea285a6b4c..dfef2bf645 100644
--- a/lib/classes/API/V1/result.php
+++ b/lib/classes/API/V1/result.php
@@ -44,9 +44,6 @@ class API_V1_result
     /** @var mixed */
     protected $response;
 
-    /** @var string */
-    protected $response_type;
-
     /** Constant for response type json */
     const FORMAT_JSON = 'json';
     /** Constant for response type yaml */
@@ -153,7 +150,7 @@ class API_V1_result
 
         $return_value = false;
 
-        switch ($this->request->getRequestFormat('json')) {
+        switch ($this->request->getRequestFormat(self::FORMAT_JSON)) {
             case self::FORMAT_JSON:
             case self::FORMAT_JSON_EXTENDED:
             default:
@@ -296,11 +293,7 @@ class API_V1_result
      */
     public function get_http_code()
     {
-        if ($this->response_type == self::FORMAT_JSONP && $this->http_code !== 500) {
-            return 200;
-        } else {
-            return $this->http_code;
-        }
+        return $this->http_code;
     }
 
     /**
diff --git a/tests/classes/api/v1/api_v1_adapterTest.php b/tests/classes/api/v1/api_v1_adapterTest.php
index c3697af9e2..124fe1a188 100644
--- a/tests/classes/api/v1/api_v1_adapterTest.php
+++ b/tests/classes/api/v1/api_v1_adapterTest.php
@@ -24,32 +24,26 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $result = $this->object->get_error_code($request, 400);
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(400, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_code($request, 403);
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(403, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_code($request, 500);
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(500, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_code($request, 405);
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(405, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_code($request, 404);
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(404, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_code($request, 401);
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(401, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
     }
 
     public function testGet_error_message()
@@ -58,32 +52,26 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $result = $this->object->get_error_message($request, API_V1_result::ERROR_BAD_REQUEST, 'detaillage');
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(400, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_message($request, API_V1_result::ERROR_FORBIDDEN, 'detaillage');
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(403, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_message($request, API_V1_result::ERROR_INTERNALSERVERERROR, 'detaillage');
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(500, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_message($request, API_V1_result::ERROR_METHODNOTALLOWED, 'detaillage');
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(405, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_message($request, API_V1_result::ERROR_NOTFOUND, 'detaillage');
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(404, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
 
         $result = $this->object->get_error_message($request, API_V1_result::ERROR_UNAUTHORIZED, 'detaillage');
         $this->assertTrue(is_array(json_decode($result->format(), true)));
         $this->assertEquals(401, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
     }
 
     public function testGet_version()
@@ -96,7 +84,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_databoxes($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -106,7 +93,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         foreach (self::$DI['app']['phraseanet.appbox']->get_databoxes() as $databox) {
             $result = $this->object->get_databox_collections($request, $databox->get_sbas_id());
             $this->assertEquals(200, $result->get_http_code());
-            $this->assertEquals('application/json', $result->get_content_type());
             $this->assertTrue(is_array(json_decode($result->format(), true)));
         }
     }
@@ -121,7 +107,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_record($request, self::$DI['record_1']->get_sbas_id(), self::$DI['record_1']->get_record_id());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -131,7 +116,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         foreach (self::$DI['app']['phraseanet.appbox']->get_databoxes() as $databox) {
             $result = $this->object->get_databox_status($request, $databox->get_sbas_id());
             $this->assertEquals(200, $result->get_http_code());
-            $this->assertEquals('application/json', $result->get_content_type());
             $this->assertTrue(is_array(json_decode($result->format(), true)));
         }
     }
@@ -142,7 +126,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         foreach (self::$DI['app']['phraseanet.appbox']->get_databoxes() as $databox) {
             $result = $this->object->get_databox_metadatas($request, $databox->get_sbas_id());
             $this->assertEquals(200, $result->get_http_code());
-            $this->assertEquals('application/json', $result->get_content_type());
             $this->assertTrue(is_array(json_decode($result->format(), true)));
         }
     }
@@ -153,7 +136,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         foreach (self::$DI['app']['phraseanet.appbox']->get_databoxes() as $databox) {
             $result = $this->object->get_databox_terms($request, $databox->get_sbas_id());
             $this->assertEquals(200, $result->get_http_code());
-            $this->assertEquals('application/json', $result->get_content_type());
             $this->assertTrue(is_array(json_decode($result->format(), true)));
         }
     }
@@ -167,7 +149,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array('record_type' => "image", 'search_type' => 0), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->search_records($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $data = json_decode($result->format(), true);
@@ -190,7 +171,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->search_records($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $data = json_decode($result->format(), true);
@@ -251,7 +231,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array('search_type' => 1), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->search_records($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $data = json_decode($result->format(), true);
@@ -283,7 +262,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array('search_type' => 1), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->search($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $data = json_decode($result->format(), true);
@@ -314,7 +292,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array('search_type' => 0), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->search($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $data = json_decode($result->format(), true);
@@ -353,7 +330,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_record_related($request, self::$DI['record_1']->get_sbas_id(), self::$DI['record_1']->get_record_id());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $data = json_decode($result->format(), true);
@@ -392,7 +368,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_record_metadatas($request, self::$DI['record_1']->get_sbas_id(), self::$DI['record_1']->get_record_id());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -403,7 +378,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_record_status($request, self::$DI['record_1']->get_sbas_id(), self::$DI['record_1']->get_record_id());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -413,7 +387,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_record_embed($request, self::$DI['record_1']->get_sbas_id(), self::$DI['record_1']->get_record_id());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -540,7 +513,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->search_baskets($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -549,7 +521,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array('name' => 'BIG BASKET'), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->create_basket($request);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $n = 0;
@@ -586,7 +557,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->delete_basket($request, $ssel_id);
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $repo = $em->getRepository('\Entities\Basket');
@@ -608,7 +578,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array(), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->get_basket($request, $basket->getId());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
     }
 
@@ -621,7 +590,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array('name' => 'PROUTO'), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->set_basket_title($request, $basket->getId());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $repository = self::$DI['app']['EM']->getRepository('\Entities\Basket');
@@ -640,7 +608,6 @@ class API_V1_adapterTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $request = new Request(array(), array(), array('description' => 'une belle description'), array(), array(), array('HTTP_Accept' => 'application/json'));
         $result = $this->object->set_basket_description($request, $basket->getId());
         $this->assertEquals(200, $result->get_http_code());
-        $this->assertEquals('application/json', $result->get_content_type());
         $this->assertTrue(is_array(json_decode($result->format(), true)));
 
         $repository = self::$DI['app']['EM']->getRepository('\Entities\Basket');
diff --git a/tests/classes/api/v1/api_v1_resultTest.php b/tests/classes/api/v1/api_v1_resultTest.php
index 08cb107422..c21b526d15 100644
--- a/tests/classes/api/v1/api_v1_resultTest.php
+++ b/tests/classes/api/v1/api_v1_resultTest.php
@@ -242,34 +242,6 @@ class API_V1_resultTest extends PhraseanetPHPUnitAuthenticatedAbstract
         $this->assertEquals($expected_value, $response->response->$field);
     }
 
-    public function testGet_content_type()
-    {
-        $server = array("HTTP_ACCEPT" => "application/json");
-        $request = new Request(array("callback" => ""), array(), array(), array(), array(), $server);
-        $api_result = new API_V1_result(self::$DI['app'], $request, $this->api);
-        $this->assertEquals("application/json", $api_result->get_content_type());
-
-        $server = array("HTTP_ACCEPT" => "application/yaml");
-        $request = new Request(array("callback" => ""), array(), array(), array(), array(), $server);
-        $api_result = new API_V1_result(self::$DI['app'], $request, $this->api);
-        $this->assertEquals('application/yaml', $api_result->get_content_type());
-
-        $server = array("HTTP_ACCEPT" => "text/yaml");
-        $request = new Request(array("callback" => ""), array(), array(), array(), array(), $server);
-        $api_result = new API_V1_result(self::$DI['app'], $request, $this->api);
-        $this->assertEquals('application/yaml', $api_result->get_content_type());
-
-        $server = array("HTTP_ACCEPT" => "");
-        $request = new Request(array("callback" => "hello"), array(), array(), array(), array(), $server);
-        $api_result = new API_V1_result(self::$DI['app'], $request, $this->api);
-        $this->assertEquals('text/javascript', $api_result->get_content_type());
-
-        $server = array("HTTP_ACCEPT" => "unknow");
-        $request = new Request(array("callback" => ""), array(), array(), array(), array(), $server);
-        $api_result = new API_V1_result(self::$DI['app'], $request, $this->api);
-        $this->assertEquals("application/json", $api_result->get_content_type());
-    }
-
     /**
      * @depends testFormatJson
      */