diff --git a/src/Symfony/Component/Console/Input/StringInput.php b/src/Symfony/Component/Console/Input/StringInput.php
index 93b1b83bb1..1bf1dc9c8e 100644
--- a/src/Symfony/Component/Console/Input/StringInput.php
+++ b/src/Symfony/Component/Console/Input/StringInput.php
@@ -37,9 +37,13 @@ class StringInput extends ArgvInput
      */
     public function __construct($input, InputDefinition $definition = null)
     {
-        parent::__construct(array(), $definition);
+        parent::__construct(array(), null);
 
         $this->setTokens($this->tokenize($input));
+
+        if (null !== $definition) {
+            $this->bind($definition);
+        }
     }
 
     /**
diff --git a/src/Symfony/Component/Console/Tests/Input/StringInputTest.php b/src/Symfony/Component/Console/Tests/Input/StringInputTest.php
index fd252c87d3..1ce5fe6274 100644
--- a/src/Symfony/Component/Console/Tests/Input/StringInputTest.php
+++ b/src/Symfony/Component/Console/Tests/Input/StringInputTest.php
@@ -35,11 +35,14 @@ class StringInputTest extends \PHPUnit_Framework_TestCase
             array(new InputOption('foo', null, InputOption::VALUE_REQUIRED))
         );
 
+        // call to bind
         $input = new StringInput('--foo=bar');
         $input->bind($definition);
-        $actual = $input->getOption('foo');
+        $this->assertEquals('bar', $input->getOption('foo'));
 
-        $this->assertEquals('bar', $actual);
+        // definition in constructor
+        $input = new StringInput('--foo=bar', $definition);
+        $this->assertEquals('bar', $input->getOption('foo'));
     }
 
     public function getTokenizeData()