diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
index 61722072e4..ed852fd041 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
@@ -21,69 +21,66 @@ use Symfony\Component\DependencyInjection\ContainerBuilder;
  */
 class UnusedTagsPass implements CompilerPassInterface
 {
-    /**
-     * whitelisted tags
-     *
-     * @var array
-     */
-    protected $whitelist = array(
-        "console.command",
-        "config_cache.resource_checker",
-        "data_collector",
-        "form.type",
-        "form.type_extension",
-        "form.type_guesser",
-        "kernel.cache_clearer",
-        "kernel.cache_warmer",
-        "kernel.event_listener",
-        "kernel.event_subscriber",
-        "kernel.fragment_renderer",
-        "monolog.logger",
-        "routing.expression_language_provider",
-        "routing.loader",
-        "security.expression_language_provider",
-        "security.remember_me_aware",
-        "security.voter",
-        "serializer.encoder",
-        "serializer.normalizer",
-        "templating.helper",
-        "translation.dumper",
-        "translation.extractor",
-        "translation.loader",
-        "twig.extension",
-        "twig.loader",
-        "validator.constraint_validator",
-        "validator.initializer",
+    private $whitelist = array(
+        'console.command',
+        'config_cache.resource_checker',
+        'data_collector',
+        'form.type',
+        'form.type_extension',
+        'form.type_guesser',
+        'kernel.cache_clearer',
+        'kernel.cache_warmer',
+        'kernel.event_listener',
+        'kernel.event_subscriber',
+        'kernel.fragment_renderer',
+        'monolog.logger',
+        'routing.expression_language_provider',
+        'routing.loader',
+        'security.expression_language_provider',
+        'security.remember_me_aware',
+        'security.voter',
+        'serializer.encoder',
+        'serializer.normalizer',
+        'templating.helper',
+        'translation.dumper',
+        'translation.extractor',
+        'translation.loader',
+        'twig.extension',
+        'twig.loader',
+        'validator.constraint_validator',
+        'validator.initializer',
     );
 
     public function process(ContainerBuilder $container)
     {
         $compiler = $container->getCompiler();
         $formatter = $compiler->getLoggingFormatter();
-        $tags = $container->findTags();
+        $tags = array_unique(array_merge($container->findTags(), $this->whitelist));
 
-        $unusedTags = $container->findUnusedTags();
-        foreach ($unusedTags as $tag) {
+        foreach ($container->findUnusedTags() as $tag) {
             // skip whitelisted tags
             if (in_array($tag, $this->whitelist)) {
                 continue;
             }
+
             // check for typos
             $candidates = array();
             foreach ($tags as $definedTag) {
                 if ($definedTag === $tag) {
                     continue;
                 }
+
                 if (false !== strpos($definedTag, $tag) || levenshtein($tag, $definedTag) <= strlen($tag) / 3) {
                     $candidates[] = $definedTag;
                 }
             }
 
             $services = array_keys($container->findTaggedServiceIds($tag));
-            $message = sprintf('Tag "%s" was defined on the service(s) %s, but was never used.', $tag, implode(',', $services));
+            $message = sprintf('Tag "%s" was defined on service(s) "%s", but was never used.', $tag, implode('", "', $services));
             if (!empty($candidates)) {
                 $message .= sprintf(' Did you mean "%s"?', implode('", "', $candidates));
             }
+
             $compiler->addLogMessage($formatter->format($this, $message));
         }
     }
diff --git a/src/Symfony/Bundle/FrameworkBundle/FrameworkBundle.php b/src/Symfony/Bundle/FrameworkBundle/FrameworkBundle.php
index 1cdf83df5d..3a96f71e11 100644
--- a/src/Symfony/Bundle/FrameworkBundle/FrameworkBundle.php
+++ b/src/Symfony/Bundle/FrameworkBundle/FrameworkBundle.php
@@ -90,9 +90,9 @@ class FrameworkBundle extends Bundle
         $container->addCompilerPass(new TranslationDumperPass());
         $container->addCompilerPass(new FragmentRendererPass(), PassConfig::TYPE_AFTER_REMOVING);
         $container->addCompilerPass(new SerializerPass());
-        $container->addCompilerPass(new UnusedTagsPass(), PassConfig::TYPE_AFTER_REMOVING);
 
         if ($container->getParameter('kernel.debug')) {
+            $container->addCompilerPass(new UnusedTagsPass(), PassConfig::TYPE_AFTER_REMOVING);
             $container->addCompilerPass(new ContainerBuilderDebugDumpPass(), PassConfig::TYPE_AFTER_REMOVING);
             $container->addCompilerPass(new CompilerDebugDumpPass(), PassConfig::TYPE_AFTER_REMOVING);
             $container->addCompilerPass(new ConfigCachePass());
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/UnusedTagsPassTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/UnusedTagsPassTest.php
new file mode 100644
index 0000000000..f354007bb9
--- /dev/null
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/UnusedTagsPassTest.php
@@ -0,0 +1,52 @@
+<?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\Bundle\FrameworkBundle\Tests\DependencyInjection\Compiler;
+
+use Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\UnusedTagsPass;
+
+class UnusedTagsPassTest extends \PHPUnit_Framework_TestCase
+{
+    public function testProcess()
+    {
+        $pass = new UnusedTagsPass();
+
+        $formatter = $this->getMock('Symfony\Component\DependencyInjection\Compiler\LoggingFormatter');
+        $formatter
+            ->expects($this->at(0))
+            ->method('format')
+            ->with($pass, 'Tag "kenrel.event_subscriber" was defined on service(s) "foo", "bar", but was never used. Did you mean "kernel.event_subscriber"?')
+        ;
+
+        $compiler = $this->getMock('Symfony\Component\DependencyInjection\Compiler\Compiler');
+        $compiler->expects($this->once())->method('getLoggingFormatter')->will($this->returnValue($formatter));
+
+        $container = $this->getMock('Symfony\Component\DependencyInjection\ContainerBuilder',
+            array('findTaggedServiceIds', 'getCompiler', 'findUnusedTags', 'findTags')
+        );
+        $container->expects($this->once())->method('getCompiler')->will($this->returnValue($compiler));
+        $container->expects($this->once())
+            ->method('findTags')
+            ->will($this->returnValue(array('kenrel.event_subscriber')));
+        $container->expects($this->once())
+            ->method('findUnusedTags')
+            ->will($this->returnValue(array('kenrel.event_subscriber', 'form.type')));
+        $container->expects($this->once())
+            ->method('findTaggedServiceIds')
+            ->with('kenrel.event_subscriber')
+            ->will($this->returnValue(array(
+                'foo' => array(),
+                'bar' => array(),
+            )));
+
+        $pass->process($container);
+    }
+}
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/LoggingFormatter.php b/src/Symfony/Component/DependencyInjection/Compiler/LoggingFormatter.php
index 6bd6161ceb..db208fa0d6 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/LoggingFormatter.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/LoggingFormatter.php
@@ -20,7 +20,7 @@ class LoggingFormatter
 {
     public function formatRemoveService(CompilerPassInterface $pass, $id, $reason)
     {
-        return $this->format($pass, sprintf('Removed service "%s"; reason: %s', $id, $reason));
+        return $this->format($pass, sprintf('Removed service "%s"; reason: %s.', $id, $reason));
     }
 
     public function formatInlineService(CompilerPassInterface $pass, $id, $target)
diff --git a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
index ca8a136d25..e3a6ea744c 100644
--- a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
+++ b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
@@ -91,7 +91,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
     private $expressionLanguageProviders = array();
 
     /**
-     * @var array with tag names used by findTaggedServiceIds
+     * @var string[] with tag names used by findTaggedServiceIds
      */
     private $usedTags = array();
 
@@ -1096,16 +1096,13 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
     }
 
     /**
-     * Returns all tags not queried by findTaggedServiceIds
+     * Returns all tags not queried by findTaggedServiceIds.
      *
-     * @return array An array of tags
+     * @return string[] An array of tags
      */
     public function findUnusedTags()
     {
-        $tags = array_values(array_diff($this->findTags(), $this->usedTags));
-        $tags = array_unique($tags);
-
-        return $tags;
+        return array_values(array_diff($this->findTags(), $this->usedTags));
     }
 
     public function addExpressionLanguageProvider(ExpressionFunctionProviderInterface $provider)