Warning: require_once(phing/input/MultipleChoiceInputRequest.php) [function.require-once]: failed to open stream: No such file or directory in /var/www/core/lib/symfony/vendor/phing/input/YesNoInputRequest.php on line 22

Fatal error: require_once() [function.require]: Failed opening required 'phing/input/MultipleChoiceInputRequest.php' (include_path='.:/usr/share/php:/usr/share/pear') in /var/www/core/lib/symfony/vendor/phing/input/YesNoInputRequest.php on line 22