diff --git a/src/Symfony/Component/Console/Input/Input.php b/src/Symfony/Component/Console/Input/Input.php
index 70291be7e9..57f2972e6f 100644
--- a/src/Symfony/Component/Console/Input/Input.php
+++ b/src/Symfony/Component/Console/Input/Input.php
@@ -37,6 +37,8 @@ abstract class Input implements InputInterface
     public function __construct(InputDefinition $definition = null)
     {
         if (null === $definition) {
+            $this->arguments = array();
+            $this->options = array();
             $this->definition = new InputDefinition();
         } else {
             $this->bind($definition);