diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php
index 79afd37527..20e6bd73d1 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php
@@ -59,14 +59,14 @@ class MainConfiguration implements ConfigurationInterface
         $rootNode
             ->children()
                 ->scalarNode('access_denied_url')->defaultNull()->example('/foo/error403')->end()
-                ->scalarNode('session_fixation_strategy')->cannotBeEmpty()->info('strategy can be: none, migrate, invalidate')->defaultValue('migrate')->end()
+                ->enumNode('session_fixation_strategy')->cannotBeEmpty()->values(array('none', 'migrate', 'invalidate'))->defaultValue('migrate')->end()
                 ->booleanNode('hide_user_not_found')->defaultTrue()->end()
                 ->booleanNode('always_authenticate_before_granting')->defaultFalse()->end()
                 ->booleanNode('erase_credentials')->defaultTrue()->end()
                 ->arrayNode('access_decision_manager')
                     ->addDefaultsIfNotSet()
                     ->children()
-                        ->scalarNode('strategy')->defaultValue('affirmative')->end()
+                        ->enumNode('strategy')->values(array('affirmative', 'consensus', 'unanimous'))->defaultValue('affirmative')->end()
                         ->booleanNode('allow_if_all_abstain')->defaultFalse()->end()
                         ->booleanNode('allow_if_equal_granted_denied')->defaultTrue()->end()
                     ->end()