Upgraded to Symfony 2.1-beta2

app/SymfonyRequirements.php

@@ -14,6 +14,17 @@
  * It can be a mandatory requirement or an optional recommendation.
  * There is a special subclass, named PhpIniRequirement, to check a php.ini configuration.
  *
+ * This file must be compatible with PHP 5.2+.
+ *
+ * ************** CAUTION **************
+ *
+ * DO NOT EDIT THIS FILE AS IT WILL BE OVERRIDEN BY COMPOSER
+ *
+ * If you want to change this file, edit the one in the
+ * SensioDistributionBundle instead.
+ *
+ * ************** CAUTION **************
+ *
  * @author Tobias Schultze <http://tobion.de>
  */
 class Requirement
@@ -386,12 +397,18 @@ class SymfonyRequirements extends RequirementCollection
         );
 
         $this->addRequirement(
-            is_dir(__DIR__.'/../vendor/symfony'),
+            is_dir(__DIR__.'/../vendor/composer'),
             'Vendor libraries must be installed',
             'Vendor libraries are missing. Install composer following instructions from <a href="http://getcomposer.org/">http://getcomposer.org/</a>. ' .
                 'Then run "<strong>php composer.phar install</strong>" to install them.'
         );
 
+        $this->addRequirement(
+            file_get_contents(__FILE__) == file_get_contents(__DIR__.'/../vendor/sensio/distribution-bundle/Sensio/Bundle/DistributionBundle/Resources/skeleton/app/SymfonyRequirements.php'),
+            'Outdated requirements file',
+            'Your requirements file is outdated. Run composer install and re-check your configuration.'
+        );
+
         $baseDir = basename(__DIR__);
         $this->addRequirement(
             is_writable(__DIR__.'/cache'),
@@ -413,7 +430,7 @@ class SymfonyRequirements extends RequirementCollection
 
         if (version_compare($installedPhpVersion, self::REQUIRED_PHP_VERSION, '>=')) {
           $this->addRequirement(
-            (in_array(date_default_timezone_get(), \DateTimeZone::listIdentifiers())),
+            (in_array(date_default_timezone_get(), DateTimeZone::listIdentifiers())),
             sprintf('Default timezone is deprecated (%s)', date_default_timezone_get()),
             'Fix your <strong>php.ini</strong> file (list of deprecated timezones http://us.php.net/manual/en/timezones.others.php).'
           );