Warning: require_once(phing/BuildException.php) [function.require-once]: failed to open stream: No such file or directory in /var/www/asociados/lib/symfony/vendor/propel-generator/classes/propel/engine/EngineException.php on line 22

Fatal error: require_once() [function.require]: Failed opening required 'phing/BuildException.php' (include_path='.:/usr/share/php:/usr/share/pear') in /var/www/asociados/lib/symfony/vendor/propel-generator/classes/propel/engine/EngineException.php on line 22