diff --git a/src/Symfony/Component/OptionsResolver/NestableOptionsResolverInterface.php b/src/Symfony/Component/OptionsResolver/NestableOptionsResolverInterface.php
new file mode 100644
index 0000000000000..4eea903efc6c7
--- /dev/null
+++ b/src/Symfony/Component/OptionsResolver/NestableOptionsResolverInterface.php
@@ -0,0 +1,26 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\OptionsResolver;
+
+/**
+ * @author Wouter J <wouter@wouterj.nl>
+ */
+interface NestableOptionsResolverInterface extends OptionsResolverInterface
+{
+    /**
+     * Sets nested options resolvers.
+     *
+     * @param array $options A list of option names as keys and instances of
+     *                       OptionsResolverInterface as values.
+     */
+    public function setNestedOptionsResolver(array $options);
+}
diff --git a/src/Symfony/Component/OptionsResolver/Options.php b/src/Symfony/Component/OptionsResolver/Options.php
index 43c81f0c33403..3b2ab2deb52fd 100644
--- a/src/Symfony/Component/OptionsResolver/Options.php
+++ b/src/Symfony/Component/OptionsResolver/Options.php
@@ -97,10 +97,10 @@ public function set($option, $value)
     /**
      * Sets the normalizer for a given option.
      *
-     * Normalizers should be closures with the following signature:
+     * Normalizers should be valid callables with the following signature:
      *
      * <code>
-     * function (Options $options, $value)
+     * function (Options $options, $value, $option)
      * </code>
      *
      * This closure will be evaluated once the option is read using
@@ -108,14 +108,18 @@ public function set($option, $value)
      * other options through the passed {@link Options} instance.
      *
      * @param string   $option     The name of the option.
-     * @param \Closure $normalizer The normalizer.
+     * @param callable $normalizer The normalizer.
      *
      * @throws OptionDefinitionException If options have already been read.
      *                                   Once options are read, the container
      *                                   becomes immutable.
      */
-    public function setNormalizer($option, \Closure $normalizer)
+    public function setNormalizer($option, $normalizer)
     {
+        if (!is_callable($normalizer)) {
+            throw new \InvalidArgumentException('Normalizers should be a valid callable.');
+        }
+
         if ($this->reading) {
             throw new OptionDefinitionException('Normalizers cannot be added anymore once options have been read.');
         }
@@ -500,11 +504,11 @@ private function normalize($option)
             throw new OptionDefinitionException(sprintf('The options "%s" have a cyclic dependency.', implode('", "', $conflicts)));
         }
 
-        /** @var \Closure $normalizer */
+        /** @var callable $normalizer */
         $normalizer = $this->normalizers[$option];
 
         $this->lock[$option] = true;
-        $this->options[$option] = $normalizer($this, array_key_exists($option, $this->options) ? $this->options[$option] : null);
+        $this->options[$option] = call_user_func($normalizer, $this, array_key_exists($option, $this->options) ? $this->options[$option] : null, $option);
         unset($this->lock[$option]);
 
         // The option is now normalized
diff --git a/src/Symfony/Component/OptionsResolver/OptionsResolver.php b/src/Symfony/Component/OptionsResolver/OptionsResolver.php
index 237ab8135f503..7c143283063c1 100644
--- a/src/Symfony/Component/OptionsResolver/OptionsResolver.php
+++ b/src/Symfony/Component/OptionsResolver/OptionsResolver.php
@@ -21,7 +21,7 @@
  * @author Bernhard Schussek <bschussek@gmail.com>
  * @author Tobias Schultze <http://tobion.de>
  */
-class OptionsResolver implements OptionsResolverInterface
+class OptionsResolver implements NestableOptionsResolverInterface
 {
     /**
      * The default option values.
@@ -53,6 +53,12 @@ class OptionsResolver implements OptionsResolverInterface
      */
     private $allowedTypes = array();
 
+    /**
+     * A list of the nested option resolvers.
+     * @var array
+     */
+    private $optionResolvers = array();
+
     /**
      * Creates a new instance.
      */
@@ -181,6 +187,37 @@ public function addAllowedTypes(array $allowedTypes)
         return $this;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function setNestedOptionsResolver(array $options)
+    {
+        $this->validateOptionsExistence($options);
+
+        foreach ($options as $option => $resolver) {
+            if (!$resolver instanceof OptionsResolverInterface) {
+                throw new \InvalidArgumentException('Nested option resolvers have to implement OptionsResolverInterface.');
+            }
+            $this->optionResolvers[$option] = $resolver;
+            $this->setNormalizers(array($option => array($this, 'nestedNormalizer')));
+        }
+
+        return $this;
+    }
+
+    /**
+     * This normalizer will be called when an option has a nested options
+     * resolver.
+     *
+     * @param Options    $options
+     * @param null|array $value
+     * @param string     $option
+     */
+    public function nestedNormalizer(Options $options, $value, $option)
+    {
+        return $this->optionResolvers[$option]->resolve($value ?: array());
+    }
+
     /**
      * {@inheritdoc}
      */
diff --git a/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php b/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php
index fc3b3fc5d38e3..cad144273b3f5 100644
--- a/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php
+++ b/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php
@@ -717,4 +717,54 @@ public function testClone()
             'three' => '3',
         ), $clone->resolve());
     }
+
+    public function testNestedResolversForRequiredOption()
+    {
+        $this->resolver->setRequired(array('db'));
+        $this->resolver->setNestedOptionsResolver(array(
+            'db' => $this->getNestedResolver(),
+        ));
+
+        $this->assertEquals(array(
+            'db' => array(
+                'dsn' => 'sqlite:app.sqlite',
+                'user' => 'root',
+                'password' => '',
+                'port' => 3306,
+            ),
+        ), $this->resolver->resolve(array(
+            'db' => array(
+                'dsn' => 'sqlite:app.sqlite',
+            ),
+        )));
+    }
+
+    /**
+     * @expectedException Symfony\Component\OptionsResolver\Exception\MissingOptionsException
+     *
+     * Nested options resolvers will always be executed, eventhough the option
+     * is missing. See {@link https://github.com/symfony/symfony/issues/9174}
+     */
+    public function testNestedResolversForOptionalOption()
+    {
+        $this->resolver->setOptional(array('db'));
+        $this->resolver->setNestedOptionsResolver(array(
+            'db' => $this->getNestedResolver(),
+        ));
+
+        $this->assertEquals(array(), $this->resolver->resolve(array()));
+    }
+
+    private function getNestedResolver()
+    {
+        $nestedResolver = new OptionsResolver();
+        $nestedResolver->setDefaults(array(
+            'user' => 'root',
+            'password' => '',
+            'port' => 3306,
+        ));
+        $nestedResolver->setRequired(array('dsn'));
+
+        return $nestedResolver;
+    }
 }

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