diff --git a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php
index 3b3b28f570..c6c3ebb284 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php
@@ -211,12 +211,8 @@ abstract class Descriptor implements DescriptorInterface
         if (is_bool($value) || is_array($value) || (null === $value)) {
             $jsonString = json_encode($value);
 
-            if (!function_exists('mb_strlen')) {
-                return substr($jsonString, 0, 60).(strlen($jsonString) > 60 ? ' ...' : '');
-            }
-
-            if (mb_strlen($jsonString) > 60) {
-                return mb_substr($jsonString, 0, 60).' ...';
+            if (preg_match('/^(.{60})./us', $jsonString, $matches)) {
+                return $matches[1].'...';
             }
 
             return $jsonString;