Usando classes do Zend Framework no Symfony

1 - incluir as classes em plugins/Zend/lib

2 - configurar o caminho no settings.yml

# Zend Framework
zend_autoload: on
zend_lib_dir: "%SF_PLUGINS_DIR%/Zend/lib"

3 - inicializar o autoload no frontendConfiguration:

/**
* @package system
* @subpackage configuration
*/
class frontendConfiguration extends sfApplicationConfiguration
{
public function configure()
{

}

public function initialize()
{
parent::initialize();
/**
* Zend Framework Autoloading
*/
if(sfConfig::get('sf_zend_autoload', true) && ($sf_zend_lib_dir = sfConfig::get('sf_zend_lib_dir'))) {
set_include_path($sf_zend_lib_dir.PATH_SEPARATOR.get_include_path());
require_once($sf_zend_lib_dir.DIRECTORY_SEPARATOR.'Zend'.DIRECTORY_SEPARATOR .'Loader.php');
spl_autoload_register(array('Zend_Loader', 'loadClass'));
}

/**
* DOMPdf Autoloading
*/
if(sfConfig::get('sf_dompdf_autoload', true) && ($sf_dompdf_lib_dir = sfConfig::get('sf_dompdf_lib_dir'))) {
set_include_path($sf_dompdf_lib_dir.PATH_SEPARATOR.get_include_path());
// require_once($sf_dompdf_lib_dir.DIRECTORY_SEPARATOR.'dompdf_config.inc.php');
// spl_autoload_register('DOMPDF_autoload');
}
}
}