diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MongoDbSessionHandlerTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MongoDbSessionHandlerTest.php
index c9eb0b38d6..979880d0a3 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MongoDbSessionHandlerTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MongoDbSessionHandlerTest.php
@@ -18,35 +18,35 @@ use Symfony\Component\HttpFoundation\Session\Storage\Handler\MongoDbSessionHandl
  */
 class MongoDbSessionHandlerTest extends \PHPUnit_Framework_TestCase
 {
-    private static $mongo;
+    /**
+     * @var \PHPUnit_Framework_MockObject_MockObject
+     */
+    private $mongo;
 
-    public static function setUpBeforeClass()
-    {
-        if (class_exists('\Mongo')) {
-            try {
-                self::$mongo = new \Mongo();
-            } catch (\Exception $e) {
-            }
-        }
-    }
+    /**
+     * @var array
+     */
+    private $options;
 
     protected function setUp()
     {
-        if (null === self::$mongo) {
-            $this->markTestSkipped('MongoDbSessionHandler requires the php "mongo" extension and a mongodb server on localhost');
+        if (!class_exists('\Mongo')) {
+            $this->markTestSkipped('MongoDbSessionHandler requires the php "mongo" extension');
         }
 
-        $this->options = array('database' => 'sf2-test', 'collection' => 'session-test');
-        $this->options = array('database' => 'sf2-test', 'collection' => 'session-test');
+        $this->mongo = $this->getMockBuilder('Mongo')
+            ->disableOriginalConstructor()
+            ->getMock();
 
-        $this->storage = new MongoDbSessionHandler(self::$mongo, $this->options);
-    }
+        $this->options = array(
+            'id_field'   => 'sess_id',
+            'data_field' => 'sess_data',
+            'time_field' => 'sess_time',
+            'database' => 'sf2-test',
+            'collection' => 'session-test'
+        );
 
-    protected function tearDown()
-    {
-        if (null !== self::$mongo) {
-            self::$mongo->dropDB($this->options['database']);
-        }
+        $this->storage = new MongoDbSessionHandler($this->mongo, $this->options);
     }
 
     public function testOpenMethodAlwaysReturnTrue()
@@ -61,39 +61,136 @@ class MongoDbSessionHandlerTest extends \PHPUnit_Framework_TestCase
 
     public function testWrite()
     {
+        $database = $this->getMockBuilder('MongoDB')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $collection = $this->getMockBuilder('MongoCollection')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $this->mongo->expects($this->once())
+            ->method('selectDB')
+            ->with($this->options['database'])
+            ->will($this->returnValue($database));
+
+        $database->expects($this->once())
+            ->method('selectCollection')
+            ->with($this->options['collection'])
+            ->will($this->returnValue($collection));
+
+        $that = $this;
+        $data = array();
+
+        $collection->expects($this->once())
+            ->method('update')
+            ->will($this->returnCallback(function($citeria, $updateData, $options) use ($that, &$data) {
+                $that->assertEquals(array($that->options['id_field'] => 'foo'), $citeria);
+                $that->assertEquals(array('upsert' => true), $options);
+
+                $data = $updateData['$set'];
+            }));
+
         $this->assertTrue($this->storage->write('foo', 'bar'));
-        $this->assertEquals('bar', $this->storage->read('foo'));
+
+        $this->assertEquals('foo', $data[$this->options['id_field']]);
+        $this->assertEquals('bar', $data[$this->options['data_field']]->bin);
     }
 
     public function testReplaceSessionData()
     {
+        $database = $this->getMockBuilder('MongoDB')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $collection = $this->getMockBuilder('MongoCollection')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $this->mongo->expects($this->once())
+            ->method('selectDB')
+            ->with($this->options['database'])
+            ->will($this->returnValue($database));
+
+        $database->expects($this->once())
+            ->method('selectCollection')
+            ->with($this->options['collection'])
+            ->will($this->returnValue($collection));
+
+        $data = array();
+
+        $collection->expects($this->exactly(2))
+            ->method('update')
+            ->will($this->returnCallback(function($citeria, $updateData, $options) use (&$data) {
+                $data = $updateData;
+            }));
+
         $this->storage->write('foo', 'bar');
         $this->storage->write('foo', 'foobar');
 
-        $coll = self::$mongo->selectDB($this->options['database'])->selectCollection($this->options['collection']);
-
-        $this->assertEquals('foobar', $this->storage->read('foo'));
-        $this->assertEquals(1, $coll->find(array('sess_id' => 'foo'))->count());
+        $this->assertEquals('foobar', $data['$set'][$this->options['data_field']]->bin);
     }
 
     public function testDestroy()
     {
-        $this->storage->write('foo', 'bar');
-        $this->storage->destroy('foo');
+        $database = $this->getMockBuilder('MongoDB')
+            ->disableOriginalConstructor()
+            ->getMock();
 
-        $this->assertEquals('', $this->storage->read('foo'));
+        $collection = $this->getMockBuilder('MongoCollection')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $this->mongo->expects($this->once())
+            ->method('selectDB')
+            ->with($this->options['database'])
+            ->will($this->returnValue($database));
+
+        $database->expects($this->once())
+            ->method('selectCollection')
+            ->with($this->options['collection'])
+            ->will($this->returnValue($collection));
+
+        $collection->expects($this->once())
+            ->method('remove')
+            ->with(
+                array($this->options['id_field'] => 'foo'),
+                array('justOne' => true)
+            );
+
+
+        $this->storage->destroy('foo');
     }
 
     public function testGc()
     {
-        $this->storage->write('foo', 'bar');
-        $this->storage->write('bar', 'foo');
+        $database = $this->getMockBuilder('MongoDB')
+            ->disableOriginalConstructor()
+            ->getMock();
 
-        $coll = self::$mongo->selectDB($this->options['database'])->selectCollection($this->options['collection']);
+        $collection = $this->getMockBuilder('MongoCollection')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $this->mongo->expects($this->once())
+            ->method('selectDB')
+            ->with($this->options['database'])
+            ->will($this->returnValue($database));
+
+        $database->expects($this->once())
+            ->method('selectCollection')
+            ->with($this->options['collection'])
+            ->will($this->returnValue($collection));
+
+        $that = $this;
+
+        $collection->expects($this->once())
+            ->method('remove')
+            ->will($this->returnCallback(function($citeria) use($that) {
+                $that->assertInstanceOf('MongoTimestamp', $citeria[$that->options['time_field']]['$lt']);
+                $that->assertGreaterThanOrEqual(time() - -1, $citeria[$that->options['time_field']]['$lt']->sec);
+            }));
 
-        $this->assertEquals(2, $coll->count());
         $this->storage->gc(-1);
-        $this->assertEquals(0, $coll->count());
-
     }
 }