diff --git a/src/Symfony/Component/HttpFoundation/Request.php b/src/Symfony/Component/HttpFoundation/Request.php
index 33b2f14e23f95..0d78cbdb1b6ee 100644
--- a/src/Symfony/Component/HttpFoundation/Request.php
+++ b/src/Symfony/Component/HttpFoundation/Request.php
@@ -655,6 +655,9 @@ public function hasSession()
     public function setSession(SessionInterface $session)
     {
         $this->session = $session;
+        if (!$this->hasPreviousSession()) {
+            $this->session->markAsEmpty();
+        }
     }
 
     /**
diff --git a/src/Symfony/Component/HttpFoundation/Session/Session.php b/src/Symfony/Component/HttpFoundation/Session/Session.php
index b0b3ff3d0bff0..464bac1f673b9 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Session.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Session.php
@@ -46,6 +46,14 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     private $attributeName;
 
+    /**
+     * True if we have no previous session (No session cookie)
+     * and nothing has been written to the session
+     *
+     * @var bool
+     */
+    private $emptySession = false;
+
     /**
      * Constructor.
      *
@@ -66,11 +74,24 @@ public function __construct(SessionStorageInterface $storage = null, AttributeBa
         $this->registerBag($flashes);
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function markAsEmpty()
+    {
+        if (!$this->emptySession && !$this->isStarted()) {
+            $this->emptySession = true;
+        }
+    }
+
+
     /**
      * {@inheritdoc}
      */
     public function start()
     {
+        $this->emptySession = false;
+
         return $this->storage->start();
     }
 
@@ -79,6 +100,8 @@ public function start()
      */
     public function has($name)
     {
+        if ($this->emptySession) {return null;}
+
         return $this->storage->getBag($this->attributeName)->has($name);
     }
 
@@ -87,6 +110,8 @@ public function has($name)
      */
     public function get($name, $default = null)
     {
+        if ($this->emptySession) {return $default;}
+
         return $this->storage->getBag($this->attributeName)->get($name, $default);
     }
 
@@ -95,6 +120,7 @@ public function get($name, $default = null)
      */
     public function set($name, $value)
     {
+        $this->emptySession = false;
         $this->storage->getBag($this->attributeName)->set($name, $value);
     }
 
@@ -103,6 +129,8 @@ public function set($name, $value)
      */
     public function all()
     {
+        if ($this->emptySession) {return array();}
+
         return $this->storage->getBag($this->attributeName)->all();
     }
 
@@ -111,6 +139,7 @@ public function all()
      */
     public function replace(array $attributes)
     {
+        $this->emptySession = false;
         $this->storage->getBag($this->attributeName)->replace($attributes);
     }
 
@@ -119,6 +148,8 @@ public function replace(array $attributes)
      */
     public function remove($name)
     {
+        if ($this->emptySession) {return null;}
+
         return $this->storage->getBag($this->attributeName)->remove($name);
     }
 
@@ -127,6 +158,7 @@ public function remove($name)
      */
     public function clear()
     {
+        if ($this->emptySession) {return null;}
         $this->storage->getBag($this->attributeName)->clear();
     }
 
@@ -145,6 +177,10 @@ public function isStarted()
      */
     public function getIterator()
     {
+        if ($this->emptySession) {
+            return new \ArrayIterator(array());
+        }
+
         return new \ArrayIterator($this->storage->getBag($this->attributeName)->all());
     }
 
@@ -155,6 +191,8 @@ public function getIterator()
      */
     public function count()
     {
+        if ($this->emptySession) {return 0;}
+
         return count($this->storage->getBag($this->attributeName)->all());
     }
 
diff --git a/src/Symfony/Component/HttpFoundation/Session/SessionInterface.php b/src/Symfony/Component/HttpFoundation/Session/SessionInterface.php
index a94fad00d6f0f..22bd514422af6 100644
--- a/src/Symfony/Component/HttpFoundation/Session/SessionInterface.php
+++ b/src/Symfony/Component/HttpFoundation/Session/SessionInterface.php
@@ -20,6 +20,14 @@
  */
 interface SessionInterface
 {
+    /**
+     * Mark this session as empty if this session has not started.
+     * This method should be called when we have no previous session
+     * (no session cookie) and then the session will be internally
+     * marked as empty, if it has not started yet.
+     */
+    public function markAsEmpty();
+
     /**
      * Starts the session storage.
      *