diff --git a/core/includes/config.inc b/core/includes/config.inc
index e704d04..95d4d83 100644
--- a/core/includes/config.inc
+++ b/core/includes/config.inc
@@ -77,17 +77,16 @@ function config_get_storage_names_with_prefix($prefix = '') {
  *   The name of the configuration object to retrieve. The name corresponds to
  *   a configuration file. For @code config(book.admin) @endcode, the config
  *   object returned will contain the contents of book.admin configuration file.
- * @param $class
- *   The class name of the config object to be returned. Defaults to
- *   ConfigObject.
+ * @param string $class
+ *   (optional) The name of the class to use for the configuration object.
  *
  * @return
  *   An instance of the class specified in the $class parameter.
  *
  * @todo Replace with DI container.
  */
-function config($name, $class = 'Drupal\Core\Config\ConfigObject') {
+function config($name, $class = NULL) {
   // @todo Do not reload an already loaded config object.
   // @todo Make it possible to skip load for known to be new config objects?
-  return ConfigFactory::get($name, $class)->load();
+  return ConfigFactory::get($name, $class);
 }
diff --git a/core/lib/Drupal/Core/Config/ConfigFactory.php b/core/lib/Drupal/Core/Config/ConfigFactory.php
index 29e9604..1004fdd 100644
--- a/core/lib/Drupal/Core/Config/ConfigFactory.php
+++ b/core/lib/Drupal/Core/Config/ConfigFactory.php
@@ -1,5 +1,10 @@
 <?php
 
+/**
+ * @file
+ * Definition of Drupal\Core\Config\ConfigFactory.
+ */
+
 namespace Drupal\Core\Config;
 
 /**
@@ -42,25 +47,45 @@ class ConfigFactory {
    *   The name of the configuration object to construct.
    * @param string $class
    *   (optional) The name of the class to use for the configuration object.
-   *   Defaults to Drupal\Core\Config\ConfigObject.
    * @param string $manager_class
    *   (optional) The name of the storage manager class to use. Defaults to
    *   Drupal\Core\Config\DrupalConfig.
    *
    * @return Drupal\Core\Config\ConfigObject
    *   A configuration object with the given $name.
-   *
-   * @todo Allow to instantiante a custom ConfigObject class for configuration
-   *   data.
    */
-  public static function get($name, $class = 'Drupal\Core\Config\ConfigObject', $manager_class = 'Drupal\Core\Config\DrupalConfig') {
+  public static function get($name, $class = NULL, $manager_class = 'Drupal\Core\Config\DrupalConfig') {
     // Instantiate the storage manager.
     if (!isset(self::$storageManagers[$manager_class])) {
       self::$storageManagers[$manager_class] = new $manager_class();
     }
+
     // Instantiate the configuration object, specific to the storage manager.
+    // @todo Config objects may need to be removed from this stack when deleted.
     if (!isset(self::$configObjects[$manager_class][$name])) {
+      // If no explicit configuration object class was passed, determine the class
+      // name to use based on the configuration data.
+      if (!isset($class)) {
+        $storage = self::$storageManagers[$manager_class]->selectStorage('read', $name);
+        $data = $storage->read($name);
+        if (!empty($data['config_class'])) {
+          $class = $data['config_class'];
+        }
+        else {
+          $class = 'Drupal\Core\Config\ConfigObject';
+        }
+      }
+
       self::$configObjects[$manager_class][$name] = new $class($name, self::$storageManagers[$manager_class]);
+
+      // If we loaded data already, set it.
+      if (isset($data)) {
+        self::$configObjects[$manager_class][$name]->setData($data !== FALSE ? $data : array());
+      }
+      // Otherwise, load it.
+      else {
+        self::$configObjects[$manager_class][$name]->load();
+      }
     }
     return self::$configObjects[$manager_class][$name];
   }