diff --git a/src/Symfony/Component/HttpFoundation/Session/Session.php b/src/Symfony/Component/HttpFoundation/Session/Session.php
index 0f507fc4ce..13c6448874 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Session.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Session.php
@@ -36,6 +36,16 @@ class Session implements SessionInterface
      */
     protected $storage;
 
+    /**
+     * @var string
+     */
+    private $flashName;
+
+    /**
+     * @var string
+     */
+    private $attributeName;
+
     /**
      * Constructor.
      *
@@ -46,8 +56,14 @@ class Session implements SessionInterface
     public function __construct(SessionStorageInterface $storage = null, AttributeBagInterface $attributes = null, FlashBagInterface $flashes = null)
     {
         $this->storage = $storage ?: new NativeSessionStorage();
-        $this->registerBag($attributes ?: new AttributeBag());
-        $this->registerBag($flashes ?: new FlashBag());
+
+        $attributeBag = $attributes ?: new AttributeBag();
+        $this->attributeName = $attributeBag->getName();
+        $this->registerBag($attributeBag);
+
+        $flashBag = $flashes ?: new FlashBag();
+        $this->flashName = $flashBag->getName();
+        $this->registerBag($flashBag);
     }
 
     /**
@@ -63,7 +79,7 @@ class Session implements SessionInterface
      */
     public function has($name)
     {
-        return $this->storage->getBag('attributes')->has($name);
+        return $this->storage->getBag($this->attributeName)->has($name);
     }
 
     /**
@@ -71,7 +87,7 @@ class Session implements SessionInterface
      */
     public function get($name, $default = null)
     {
-        return $this->storage->getBag('attributes')->get($name, $default);
+        return $this->storage->getBag($this->attributeName)->get($name, $default);
     }
 
     /**
@@ -79,7 +95,7 @@ class Session implements SessionInterface
      */
     public function set($name, $value)
     {
-        $this->storage->getBag('attributes')->set($name, $value);
+        $this->storage->getBag($this->attributeName)->set($name, $value);
     }
 
     /**
@@ -87,7 +103,7 @@ class Session implements SessionInterface
      */
     public function all()
     {
-        return $this->storage->getBag('attributes')->all();
+        return $this->storage->getBag($this->attributeName)->all();
     }
 
     /**
@@ -95,7 +111,7 @@ class Session implements SessionInterface
      */
     public function replace(array $attributes)
     {
-        $this->storage->getBag('attributes')->replace($attributes);
+        $this->storage->getBag($this->attributeName)->replace($attributes);
     }
 
     /**
@@ -103,7 +119,7 @@ class Session implements SessionInterface
      */
     public function remove($name)
     {
-        return $this->storage->getBag('attributes')->remove($name);
+        return $this->storage->getBag($this->attributeName)->remove($name);
     }
 
     /**
@@ -111,7 +127,7 @@ class Session implements SessionInterface
      */
     public function clear()
     {
-        $this->storage->getBag('attributes')->clear();
+        $this->storage->getBag($this->attributeName)->clear();
     }
 
     /**
@@ -201,7 +217,7 @@ class Session implements SessionInterface
      */
     public function getFlashBag()
     {
-        return $this->getBag('flashes');
+        return $this->getBag($this->flashName);
     }
 
     // the following methods are kept for compatibility with Symfony 2.0 (they will be removed for Symfony 2.3)