diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
index 8457656f08..5afc9b45e1 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
@@ -150,7 +150,7 @@ EOF
         // save the files
         if ($input->getOption('force') === true) {
             $output->writeln('Writing files');
-            $writer->writeTranslations($operation->getResult(), $input->getOption('output-format'), array('path' => $bundleTransPath));
+            $writer->writeTranslations($operation->getResult(), $input->getOption('output-format'), array('path' => $bundleTransPath, 'default_locale' => $this->getContainer()->getParameter('kernel.default_locale')));
         }
     }
 }
diff --git a/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php b/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php
index bd9b01255e..32a9c6b92b 100644
--- a/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php
@@ -20,6 +20,25 @@ use Symfony\Component\Translation\MessageCatalogue;
  */
 class XliffFileDumper extends FileDumper
 {
+    /**
+     * @var string
+     */
+    private $defaultLocale;
+
+    /**
+     * {@inheritdoc}
+     */
+    public function dump(MessageCatalogue $messages, $options = array())
+    {
+        if (array_key_exists('default_locale', $options)) {
+            $this->defaultLocale = $options['default_locale'];
+        } else {
+            $this->defaultLocale = \Locale::getDefault();
+        }
+
+        parent::dump($messages, $options);
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -33,7 +52,8 @@ class XliffFileDumper extends FileDumper
         $xliff->setAttribute('xmlns', 'urn:oasis:names:tc:xliff:document:1.2');
 
         $xliffFile = $xliff->appendChild($dom->createElement('file'));
-        $xliffFile->setAttribute('source-language', $messages->getLocale());
+        $xliffFile->setAttribute('source-language', str_replace('_', '-', $this->defaultLocale));
+        $xliffFile->setAttribute('target-language', str_replace('_', '-', $messages->getLocale()));
         $xliffFile->setAttribute('datatype', 'plaintext');
         $xliffFile->setAttribute('original', 'file.ext');
 
diff --git a/src/Symfony/Component/Translation/Tests/Dumper/XliffFileDumperTest.php b/src/Symfony/Component/Translation/Tests/Dumper/XliffFileDumperTest.php
index daf0f7a37d..1335512bf1 100644
--- a/src/Symfony/Component/Translation/Tests/Dumper/XliffFileDumperTest.php
+++ b/src/Symfony/Component/Translation/Tests/Dumper/XliffFileDumperTest.php
@@ -18,17 +18,17 @@ class XliffFileDumperTest extends \PHPUnit_Framework_TestCase
 {
     public function testDump()
     {
-        $catalogue = new MessageCatalogue('en');
+        $catalogue = new MessageCatalogue('en_US');
         $catalogue->add(array('foo' => 'bar', 'key' => ''));
         $catalogue->setMetadata('foo', array('notes' => array(array('priority' => 1, 'from' => 'bar', 'content' => 'baz'))));
         $catalogue->setMetadata('key', array('notes' => array(array('content' => 'baz'), array('content' => 'qux'))));
 
         $tempDir = sys_get_temp_dir();
         $dumper = new XliffFileDumper();
-        $dumper->dump($catalogue, array('path' => $tempDir));
+        $dumper->dump($catalogue, array('path' => $tempDir, 'default_locale' => 'fr_FR'));
 
-        $this->assertEquals(file_get_contents(__DIR__.'/../fixtures/resources-clean.xlf'), file_get_contents($tempDir.'/messages.en.xlf'));
+        $this->assertEquals(file_get_contents(__DIR__.'/../fixtures/resources-clean.xlf'), file_get_contents($tempDir.'/messages.en_US.xlf'));
 
-        unlink($tempDir.'/messages.en.xlf');
+        unlink($tempDir.'/messages.en_US.xlf');
     }
 }
diff --git a/src/Symfony/Component/Translation/Tests/fixtures/resources-clean.xlf b/src/Symfony/Component/Translation/Tests/fixtures/resources-clean.xlf
index 3c38d3d19a..3898821804 100644
--- a/src/Symfony/Component/Translation/Tests/fixtures/resources-clean.xlf
+++ b/src/Symfony/Component/Translation/Tests/fixtures/resources-clean.xlf
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <xliff xmlns="urn:oasis:names:tc:xliff:document:1.2" version="1.2">
-  <file source-language="en" datatype="plaintext" original="file.ext">
+  <file source-language="fr-FR" target-language="en-US" datatype="plaintext" original="file.ext">
     <body>
       <trans-unit id="acbd18db4cc2f85cedef654fccc4a4d8" resname="foo">
         <source>foo</source>