diff --git a/DependencyInjection/ExerciseHTMLPurifierExtension.php b/DependencyInjection/ExerciseHTMLPurifierExtension.php
index 2b720f8e..ab208509 100644
--- a/DependencyInjection/ExerciseHTMLPurifierExtension.php
+++ b/DependencyInjection/ExerciseHTMLPurifierExtension.php
@@ -37,17 +37,34 @@ public function load(array $configs, ContainerBuilder $container)
 
         foreach ($configs as $name => $config) {
             $configDefinition = new Definition('%exercise_html_purifier.config.class%');
-            $configDefinition->setFactoryClass('%exercise_html_purifier.config.class%');
-
-            if ('default' === $name) {
-                $configDefinition
-                    ->setFactoryMethod('create')
-                    ->addArgument($config);
-            } else {
-                $configDefinition
-                    ->setFactoryMethod('inherit')
-                    ->addArgument(new Reference('exercise_html_purifier.config.default'))
-                    ->addMethodCall('loadArray', array($config));
+			
+            // Handle Symfony >= 2.7
+            if (method_exists($configDefinition, 'setFactory')) {
+                if ('default' === $name) {
+                    $configDefinition
+                        ->setFactory(array('%exercise_html_purifier.config.class%', 'create'))
+                        ->addArgument($config);
+                } else {
+                    $configDefinition
+                        ->setFactory(array('%exercise_html_purifier.config.class%', 'inherit'))
+                        ->addArgument(new Reference('exercise_html_purifier.config.default'))
+                        ->addMethodCall('loadArray', array($config));
+                }
+            }
+            // Handle Symfony < 2.7
+            else {
+                $configDefinition->setFactoryClass('%exercise_html_purifier.config.class%');
+
+                if ('default' === $name) {
+                    $configDefinition
+                        ->setFactoryMethod('create')
+                        ->addArgument($config);
+                } else {
+                    $configDefinition
+                        ->setFactoryMethod('inherit')
+                        ->addArgument(new Reference('exercise_html_purifier.config.default'))
+                        ->addMethodCall('loadArray', array($config));
+                }
             }
 
             $configId = 'exercise_html_purifier.config.' . $name;