/**
* Primero, creas una carpeta en el root se llama 'templates' y
* los mueves las templates que deseas compartir alli
*/

// apps/app1/config/ap1Configuration.class.php
class appNameConfiguration extends sfApplicationConfiguration {
public function configure() {
sfConfig::set('sf_app_template_dir', sfConfig::get('sf_root_dir') . '/templates');
}
}

// apps/app2/config/ap2Configuration.class.php
class app2Configuration extends sfApplicationConfiguration {
public function configure() {
sfConfig::set('sf_app_template_dir', sfConfig::get('sf_root_dir') . '/templates');
}

}

Read more: http://feeds.dzone.com/~r/dzone/snippets/~3/Bhd1vEopgr0/13695