Warning: require_once(phing/system/io/Writer.php) [function.require-once]: failed to open stream: No such file or directory in /var/www/pyg/lib/symfony/vendor/phing/util/LogWriter.php on line 23

Fatal error: require_once() [function.require]: Failed opening required 'phing/system/io/Writer.php' (include_path='.:/usr/share/php:/usr/share/pear') in /var/www/pyg/lib/symfony/vendor/phing/util/LogWriter.php on line 23