diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
index 06f58ee48b..d192a89281 100644
--- a/src/Symfony/Component/HttpKernel/Kernel.php
+++ b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -700,7 +700,6 @@ abstract class Kernel implements KernelInterface, TerminableInterface
         foreach ($this->bundles as $bundle) {
             if ($extension = $bundle->getContainerExtension()) {
                 $container->registerExtension($extension);
-                $extensions[] = $extension->getAlias();
             }
 
             if ($this->debug) {
@@ -714,6 +713,10 @@ abstract class Kernel implements KernelInterface, TerminableInterface
 
         $this->build($container);
 
+        foreach ($container->getExtensions() as $extension) {
+            $extensions[] = $extension->getAlias();
+        }
+
         // ensure these extensions are implicitly loaded
         $container->getCompilerPassConfig()->setMergePass(new MergeExtensionConfigurationPass($extensions));
     }