diff --git a/src/Symfony/Bridge/Twig/TwigEngine.php b/src/Symfony/Bridge/Twig/TwigEngine.php
index 1ac9d0102e..760461b5be 100644
--- a/src/Symfony/Bridge/Twig/TwigEngine.php
+++ b/src/Symfony/Bridge/Twig/TwigEngine.php
@@ -112,7 +112,7 @@ class TwigEngine implements EngineInterface, StreamingEngineInterface
      * @param string|TemplateReferenceInterface|\Twig_Template $name A template name or an instance of
      *                                                               TemplateReferenceInterface or \Twig_Template
      *
-     * @return \Twig_TemplateInterface A \Twig_TemplateInterface instance
+     * @return \Twig_Template A \Twig_Template instance
      *
      * @throws \InvalidArgumentException if the template does not exist
      */
diff --git a/src/Symfony/Bundle/WebProfilerBundle/Profiler/TemplateManager.php b/src/Symfony/Bundle/WebProfilerBundle/Profiler/TemplateManager.php
index 91938e9be5..ff5dce56f9 100644
--- a/src/Symfony/Bundle/WebProfilerBundle/Profiler/TemplateManager.php
+++ b/src/Symfony/Bundle/WebProfilerBundle/Profiler/TemplateManager.php
@@ -67,7 +67,7 @@ class TemplateManager
      *
      * @param Profile $profile
      *
-     * @return Twig_Template[]
+     * @return \Twig_Template[]
      *
      * @deprecated not used anymore internally
      */
diff --git a/src/Symfony/Component/HttpKernel/EventListener/TestSessionListener.php b/src/Symfony/Component/HttpKernel/EventListener/TestSessionListener.php
index 8fc8e57579..19a61f169b 100644
--- a/src/Symfony/Component/HttpKernel/EventListener/TestSessionListener.php
+++ b/src/Symfony/Component/HttpKernel/EventListener/TestSessionListener.php
@@ -12,6 +12,7 @@
 namespace Symfony\Component\HttpKernel\EventListener;
 
 use Symfony\Component\HttpFoundation\Cookie;
+use Symfony\Component\HttpFoundation\Session\SessionInterface;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
diff --git a/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php b/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php
index 66bed137a4..be2de7b6f1 100644
--- a/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php
@@ -79,12 +79,12 @@ class YamlFileLoader extends FileLoader
 
                 if (isset($data['groups'])) {
                     if (!is_array($data['groups'])) {
-                        throw new MappingException('The "groups" key must be an array of strings in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName());
+                        throw new MappingException(sprintf('The "groups" key must be an array of strings in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName()));
                     }
 
                     foreach ($data['groups'] as $group) {
                         if (!is_string($group)) {
-                            throw new MappingException('Group names must be strings in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName());
+                            throw new MappingException(sprintf('Group names must be strings in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName()));
                         }
 
                         $attributeMetadata->addGroup($group);