diff --git a/src/Symfony/Component/Intl/NumberFormatter/StubNumberFormatter.php b/src/Symfony/Component/Intl/NumberFormatter/StubNumberFormatter.php
index f930d41b1e..b34ca11ad3 100644
--- a/src/Symfony/Component/Intl/NumberFormatter/StubNumberFormatter.php
+++ b/src/Symfony/Component/Intl/NumberFormatter/StubNumberFormatter.php
@@ -300,7 +300,7 @@ class StubNumberFormatter
             return $this->format($value);
         }
 
-        $symbol = Intl::getCurrencyBundle()->getCurrencySymbol('en', $currency);
+        $symbol = Intl::getCurrencyBundle()->getCurrencySymbol($currency, 'en');
         $fractionDigits = Intl::getCurrencyBundle()->getFractionDigits($currency);
 
         $value = $this->roundCurrency($value, $currency);
diff --git a/src/Symfony/Component/Intl/README.md b/src/Symfony/Component/Intl/README.md
index 33bef34531..a14a2a0118 100644
--- a/src/Symfony/Component/Intl/README.md
+++ b/src/Symfony/Component/Intl/README.md
@@ -55,13 +55,13 @@ Numbers can be formatted with the [`\NumberFormatter`] [3] class. The following
 methods are supported. All other methods are not supported and will throw an
 exception when used.
 
-##### __construct($locale = 'en', $style = null, $pattern = null)
+##### __construct($locale = $style = null, $pattern = null)
 
 The only supported locale is "en". The supported styles are
 `\NumberFormatter::DECIMAL` and `\NumberFormatter::CURRENCY`. The argument
 `$pattern` may not be used.
 
-##### ::create($locale = 'en', $style = null, $pattern = null)
+##### ::create($locale = $style = null, $pattern = null)
 
 See `__construct()`.
 
@@ -115,19 +115,19 @@ Languages and Scripts
 The translations of language and script names can be found in the language
 bundle.
 
-    $languages = Intl::getLanguageBundle()->getLanguageNames('en');
+    $languages = Intl::getLanguageBundle()->getLanguageNames();
     // => array('ab' => 'Abkhazian', ...)
 
-    $language = Intl::getLanguageBundle()->getLanguageName('en', 'de');
+    $language = Intl::getLanguageBundle()->getLanguageName('de');
     // => 'German'
 
-    $language = Intl::getLanguageBundle()->getLanguageName('en', 'de', 'AT);
+    $language = Intl::getLanguageBundle()->getLanguageName('de', 'AT);
     // => 'Austrian German'
 
-    $scripts = Intl::getLanguageBundle()->getScriptNames('en');
+    $scripts = Intl::getLanguageBundle()->getScriptNames();
     // => array('Arab' => 'Arabic', ...)
 
-    $script = Intl::getLanguageBundle()->getScriptName('en', 'Hans');
+    $script = Intl::getLanguageBundle()->getScriptName('Hans');
     // => 'Simplified'
 
 Countries
@@ -135,10 +135,10 @@ Countries
 
 The translations of country names can be found in the region bundle.
 
-    $countries = Intl::getRegionBundle()->getCountryNames('en');
+    $countries = Intl::getRegionBundle()->getCountryNames();
     // => array('AF' => 'Afghanistan', ...)
 
-    $country = Intl::getRegionBundle()->getCountryName('en', 'GB');
+    $country = Intl::getRegionBundle()->getCountryName('GB');
     // => 'United Kingdom'
 
 Locales
@@ -146,10 +146,10 @@ Locales
 
 The translations of locale names can be found in the locale bundle.
 
-    $locales = Intl::getLocaleBundle()->getLocaleNames('en');
+    $locales = Intl::getLocaleBundle()->getLocaleNames();
     // => array('af' => 'Afrikaans', ...)
 
-    $locale = Intl::getLocaleBundle()->getLocaleName('en', 'zh_Hans_MO');
+    $locale = Intl::getLocaleBundle()->getLocaleName('zh_Hans_MO');
     // => 'Chinese (Simplified, Macau SAR China)'
 
 Currencies
@@ -158,13 +158,13 @@ Currencies
 The translations of currency names and other currency-related information can
 be found in the currency bundle.
 
-    $currencies = Intl::getCurrencyBundle()->getCurrencyNames('en');
+    $currencies = Intl::getCurrencyBundle()->getCurrencyNames();
     // => array('AFN' => 'Afghan Afghani', ...)
 
-    $currency = Intl::getCurrencyBundle()->getCurrencyNames('en', 'INR');
+    $currency = Intl::getCurrencyBundle()->getCurrencyNames('INR');
     // => 'Indian Rupee'
 
-    $symbol = Intl::getCurrencyBundle()->getCurrencyNames('en', 'INR');
+    $symbol = Intl::getCurrencyBundle()->getCurrencyNames('INR');
     // => '₹'
 
     $fractionDigits = Intl::getCurrencyBundle()->getFractionDigits('INR');
diff --git a/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundle.php b/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundle.php
index c32e2c4980..6f2a0ed395 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundle.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundle.php
@@ -29,24 +29,36 @@ class CurrencyBundle extends AbstractBundle implements CurrencyBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getCurrencySymbol($locale, $currency)
+    public function getCurrencySymbol($currency, $locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         return $this->readEntry($locale, array('Currencies', $currency, static::INDEX_SYMBOL));
     }
 
     /**
      * {@inheritdoc}
      */
-    public function getCurrencyName($locale, $currency)
+    public function getCurrencyName($currency, $locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         return $this->readEntry($locale, array('Currencies', $currency, static::INDEX_NAME));
     }
 
     /**
      * {@inheritdoc}
      */
-    public function getCurrencyNames($locale)
+    public function getCurrencyNames($locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         if (null === ($currencies = $this->readEntry($locale, array('Currencies')))) {
             return array();
         }
diff --git a/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundleInterface.php b/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundleInterface.php
index 596f6e207d..65eeeaab69 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundleInterface.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/CurrencyBundleInterface.php
@@ -21,31 +21,34 @@ interface CurrencyBundleInterface extends ResourceBundleInterface
     /**
      * Returns the symbol used for a currency.
      *
-     * @param string $locale   The locale to return the result in.
      * @param string $currency A currency code (e.g. "EUR").
+     * @param string $locale   Optional. The locale to return the result in.
+     *                         Defaults to {@link \Locale::getLocale()}.
      *
      * @return string|null The currency symbol or NULL if not found.
      */
-    public function getCurrencySymbol($locale, $currency);
+    public function getCurrencySymbol($currency, $locale = null);
 
     /**
      * Returns the name of a currency.
      *
-     * @param string $locale   The locale to return the name in.
      * @param string $currency A currency code (e.g. "EUR").
+     * @param string $locale   Optional. The locale to return the name in.
+     *                         Defaults to {@link \Locale::getLocale()}.
      *
      * @return string|null The name of the currency or NULL if not found.
      */
-    public function getCurrencyName($locale, $currency);
+    public function getCurrencyName($currency, $locale = null);
 
     /**
      * Returns the names of all known currencies.
      *
-     * @param string $locale The locale to return the names in.
+     * @param string $locale Optional. The locale to return the names in.
+     *                       Defaults to {@link \Locale::getLocale()}.
      *
      * @return string[] A list of currency names indexed by currency codes.
      */
-    public function getCurrencyNames($locale);
+    public function getCurrencyNames($locale = null);
 
     /**
      * Returns the number of digits after the comma of a currency.
diff --git a/src/Symfony/Component/Intl/ResourceBundle/LanguageBundle.php b/src/Symfony/Component/Intl/ResourceBundle/LanguageBundle.php
index 1c3dfced57..01adaed03a 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/LanguageBundle.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/LanguageBundle.php
@@ -21,8 +21,12 @@ class LanguageBundle extends AbstractBundle implements LanguageBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getLanguageName($locale, $lang, $region = null)
+    public function getLanguageName($lang, $region = null, $locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         if (null === ($languages = $this->readEntry($locale, array('Languages')))) {
             return array();
         }
@@ -39,8 +43,12 @@ class LanguageBundle extends AbstractBundle implements LanguageBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getLanguageNames($locale)
+    public function getLanguageNames($locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         if (null === ($languages = $this->readEntry($locale, array('Languages')))) {
             return array();
         }
@@ -55,8 +63,12 @@ class LanguageBundle extends AbstractBundle implements LanguageBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getScriptName($locale, $script, $lang = null)
+    public function getScriptName($script, $lang = null, $locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         $data = $this->read($locale);
 
         // Some languages are translated together with their script,
@@ -84,8 +96,12 @@ class LanguageBundle extends AbstractBundle implements LanguageBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getScriptNames($locale)
+    public function getScriptNames($locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         if (null === ($scripts = $this->readEntry($locale, array('Scripts')))) {
             return array();
         }
diff --git a/src/Symfony/Component/Intl/ResourceBundle/LanguageBundleInterface.php b/src/Symfony/Component/Intl/ResourceBundle/LanguageBundleInterface.php
index 62a0eba250..57c18ef6fc 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/LanguageBundleInterface.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/LanguageBundleInterface.php
@@ -21,40 +21,44 @@ interface LanguageBundleInterface extends ResourceBundleInterface
     /**
      * Returns the name of a language.
      *
-     * @param string      $locale The locale to return the name in.
      * @param string      $lang   A language code (e.g. "en").
      * @param string|null $region Optional. A region code (e.g. "US").
+     * @param string      $locale Optional. The locale to return the name in.
+     *                            Defaults to {@link \Locale::getLocale()}.
      *
      * @return string|null The name of the language or NULL if not found.
      */
-    public function getLanguageName($locale, $lang, $region = null);
+    public function getLanguageName($lang, $region = null, $locale = null);
 
     /**
      * Returns the names of all known languages.
      *
-     * @param string $locale The locale to return the names in.
+     * @param string $locale Optional. The locale to return the names in.
+     *                       Defaults to {@link \Locale::getLocale()}.
      *
      * @return string[] A list of language names indexed by language codes.
      */
-    public function getLanguageNames($locale);
+    public function getLanguageNames($locale = null);
 
     /**
      * Returns the name of a script.
      *
-     * @param string $locale The locale to return the name in.
      * @param string $script A script code (e.g. "Hans").
      * @param string $lang   Optional. A language code (e.g. "zh").
+     * @param string $locale Optional. The locale to return the name in.
+     *                       Defaults to {@link \Locale::getLocale()}.
      *
      * @return string|null The name of the script or NULL if not found.
      */
-    public function getScriptName($locale, $script, $lang = null);
+    public function getScriptName($script, $lang = null, $locale = null);
 
     /**
      * Returns the names of all known scripts.
      *
-     * @param string $locale The locale to return the names in.
+     * @param string $locale Optional. The locale to return the names in.
+     *                       Defaults to {@link \Locale::getLocale()}.
      *
      * @return string[] A list of script names indexed by script codes.
      */
-    public function getScriptNames($locale);
+    public function getScriptNames($locale = null);
 }
diff --git a/src/Symfony/Component/Intl/ResourceBundle/LocaleBundle.php b/src/Symfony/Component/Intl/ResourceBundle/LocaleBundle.php
index 3f50d876db..6f6cdfcb18 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/LocaleBundle.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/LocaleBundle.php
@@ -21,16 +21,24 @@ class LocaleBundle extends AbstractBundle implements LocaleBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getLocaleName($locale, $ofLocale)
+    public function getLocaleName($ofLocale, $locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         return $this->readEntry($locale, array('Locales', $ofLocale));
     }
 
     /**
      * {@inheritdoc}
      */
-    public function getLocaleNames($locale)
+    public function getLocaleNames($locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         if (null === ($locales = $this->readEntry($locale, array('Locales')))) {
             return array();
         }
diff --git a/src/Symfony/Component/Intl/ResourceBundle/LocaleBundleInterface.php b/src/Symfony/Component/Intl/ResourceBundle/LocaleBundleInterface.php
index d7e536486a..8f30595231 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/LocaleBundleInterface.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/LocaleBundleInterface.php
@@ -21,19 +21,21 @@ interface LocaleBundleInterface extends ResourceBundleInterface
     /**
      * Returns the name of a locale.
      *
-     * @param string $locale   The locale to return the name in.
      * @param string $ofLocale The locale to return the name of (e.g. "de_AT").
+     * @param string $locale   Optional. The locale to return the name in.
+     *                         Defaults to {@link \Locale::getLocale()}.
      *
      * @return string|null The name of the locale or NULL if not found.
      */
-    public function getLocaleName($locale, $ofLocale);
+    public function getLocaleName($ofLocale, $locale = null);
 
     /**
      * Returns the names of all known locales.
      *
-     * @param string $locale The locale to return the name in.
+     * @param string $locale Optional. The locale to return the names in.
+     *                       Defaults to {@link \Locale::getLocale()}.
      *
      * @return string[] A list of locale names indexed by locale codes.
      */
-    public function getLocaleNames($locale);
+    public function getLocaleNames($locale = null);
 }
diff --git a/src/Symfony/Component/Intl/ResourceBundle/RegionBundle.php b/src/Symfony/Component/Intl/ResourceBundle/RegionBundle.php
index 58ccfd4dc7..a3cd9bd39a 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/RegionBundle.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/RegionBundle.php
@@ -21,16 +21,24 @@ class RegionBundle extends AbstractBundle implements RegionBundleInterface
     /**
      * {@inheritdoc}
      */
-    public function getCountryName($locale, $country)
+    public function getCountryName($country, $locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         return $this->readEntry($locale, array('Countries', $country));
     }
 
     /**
      * {@inheritdoc}
      */
-    public function getCountryNames($locale)
+    public function getCountryNames($locale = null)
     {
+        if (null === $locale) {
+            $locale = \Locale::getDefault();
+        }
+
         if (null === ($countries = $this->readEntry($locale, array('Countries')))) {
             return array();
         }
diff --git a/src/Symfony/Component/Intl/ResourceBundle/RegionBundleInterface.php b/src/Symfony/Component/Intl/ResourceBundle/RegionBundleInterface.php
index 835748b568..9fb6c9ec06 100644
--- a/src/Symfony/Component/Intl/ResourceBundle/RegionBundleInterface.php
+++ b/src/Symfony/Component/Intl/ResourceBundle/RegionBundleInterface.php
@@ -21,19 +21,21 @@ interface RegionBundleInterface extends ResourceBundleInterface
     /**
      * Returns the name of a country.
      *
-     * @param string $locale  The locale to return the name in.
      * @param string $country A country code (e.g. "US").
+     * @param string $locale  Optional. The locale to return the name in.
+     *                        Defaults to {@link \Locale::getLocale()}.
      *
      * @return string|null The name of the country or NULL if not found.
      */
-    public function getCountryName($locale, $country);
+    public function getCountryName($country, $locale = null);
 
     /**
      * Returns the names of all known countries.
      *
-     * @param string $locale The locale to return the names in.
+     * @param string $locale Optional. The locale to return the names in.
+     *                       Defaults to {@link \Locale::getLocale()}.
      *
      * @return string[] A list of country names indexed by country codes.
      */
-    public function getCountryNames($locale);
+    public function getCountryNames($locale = null);
 }
diff --git a/src/Symfony/Component/Intl/Tests/ResourceBundle/CurrencyBundleTest.php b/src/Symfony/Component/Intl/Tests/ResourceBundle/CurrencyBundleTest.php
index 4ee708a9fc..b66a6727bf 100644
--- a/src/Symfony/Component/Intl/Tests/ResourceBundle/CurrencyBundleTest.php
+++ b/src/Symfony/Component/Intl/Tests/ResourceBundle/CurrencyBundleTest.php
@@ -43,7 +43,7 @@ class CurrencyBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en', array('Currencies', 'EUR', 1))
             ->will($this->returnValue('€'));
 
-        $this->assertSame('€', $this->bundle->getCurrencySymbol('en', 'EUR'));
+        $this->assertSame('€', $this->bundle->getCurrencySymbol('EUR', 'en'));
     }
 
     public function testGetCurrencyName()
@@ -53,7 +53,7 @@ class CurrencyBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en', array('Currencies', 'EUR', 0))
             ->will($this->returnValue('Euro'));
 
-        $this->assertSame('Euro', $this->bundle->getCurrencyName('en', 'EUR'));
+        $this->assertSame('Euro', $this->bundle->getCurrencyName('EUR', 'en'));
     }
 
     public function testGetCurrencyNames()
diff --git a/src/Symfony/Component/Intl/Tests/ResourceBundle/LanguageBundleTest.php b/src/Symfony/Component/Intl/Tests/ResourceBundle/LanguageBundleTest.php
index a14a101a57..a8a6662155 100644
--- a/src/Symfony/Component/Intl/Tests/ResourceBundle/LanguageBundleTest.php
+++ b/src/Symfony/Component/Intl/Tests/ResourceBundle/LanguageBundleTest.php
@@ -48,7 +48,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en', array('Languages'))
             ->will($this->returnValue($languages));
 
-        $this->assertSame('German', $this->bundle->getLanguageName('en', 'de'));
+        $this->assertSame('German', $this->bundle->getLanguageName('de', 'en'));
     }
 
     public function testGetLanguageNameWithRegion()
@@ -64,7 +64,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en', array('Languages'))
             ->will($this->returnValue($languages));
 
-        $this->assertSame('British English', $this->bundle->getLanguageName('en', 'en', 'GB'));
+        $this->assertSame('British English', $this->bundle->getLanguageName('en', 'GB', 'en'));
     }
 
     public function testGetLanguageNameWithUntranslatedRegion()
@@ -79,7 +79,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en', array('Languages'))
             ->will($this->returnValue($languages));
 
-        $this->assertSame('English', $this->bundle->getLanguageName('en', 'en', 'US'));
+        $this->assertSame('English', $this->bundle->getLanguageName('en', 'US', 'en'));
     }
 
     public function testGetLanguageNames()
@@ -115,7 +115,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en')
             ->will($this->returnValue($data));
 
-        $this->assertSame('latin', $this->bundle->getScriptName('en', 'Latn'));
+        $this->assertSame('latin', $this->bundle->getScriptName('Latn', 'en'));
     }
 
     public function testGetScriptNameIncludedInLanguage()
@@ -138,7 +138,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->will($this->returnValue($data));
 
         // Null because the script is included in the language anyway
-        $this->assertNull($this->bundle->getScriptName('en', 'Hans', 'zh'));
+        $this->assertNull($this->bundle->getScriptName('Hans', 'zh', 'en'));
     }
 
     public function testGetScriptNameIncludedInLanguageInBraces()
@@ -160,7 +160,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en')
             ->will($this->returnValue($data));
 
-        $this->assertSame('simplified', $this->bundle->getScriptName('en', 'Hans', 'zh'));
+        $this->assertSame('simplified', $this->bundle->getScriptName('Hans', 'zh', 'en'));
     }
 
     public function testGetScriptNameNoScriptsBlock()
@@ -177,7 +177,7 @@ class LanguageBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en')
             ->will($this->returnValue($data));
 
-        $this->assertNull($this->bundle->getScriptName('en', 'Latn'));
+        $this->assertNull($this->bundle->getScriptName('Latn', 'en'));
     }
 
     public function testGetScriptNames()
diff --git a/src/Symfony/Component/Intl/Tests/ResourceBundle/LocaleBundleTest.php b/src/Symfony/Component/Intl/Tests/ResourceBundle/LocaleBundleTest.php
index b323362374..0ff288ddab 100644
--- a/src/Symfony/Component/Intl/Tests/ResourceBundle/LocaleBundleTest.php
+++ b/src/Symfony/Component/Intl/Tests/ResourceBundle/LocaleBundleTest.php
@@ -44,7 +44,7 @@ class LocaleBundleTest extends \PHPUnit_Framework_TestCase
             ->will($this->returnValue('German (Austria)'));
 
 
-        $this->assertSame('German (Austria)', $this->bundle->getLocaleName('en', 'de_AT'));
+        $this->assertSame('German (Austria)', $this->bundle->getLocaleName('de_AT', 'en'));
     }
 
     public function testGetLocaleNames()
diff --git a/src/Symfony/Component/Intl/Tests/ResourceBundle/RegionBundleTest.php b/src/Symfony/Component/Intl/Tests/ResourceBundle/RegionBundleTest.php
index 23ed8baef3..40a7692cf4 100644
--- a/src/Symfony/Component/Intl/Tests/ResourceBundle/RegionBundleTest.php
+++ b/src/Symfony/Component/Intl/Tests/ResourceBundle/RegionBundleTest.php
@@ -43,7 +43,7 @@ class RegionBundleTest extends \PHPUnit_Framework_TestCase
             ->with(self::RES_DIR, 'en', array('Countries', 'AT'))
             ->will($this->returnValue('Austria'));
 
-        $this->assertSame('Austria', $this->bundle->getCountryName('en', 'AT'));
+        $this->assertSame('Austria', $this->bundle->getCountryName('AT', 'en'));
     }
 
     public function testGetCountryNames()