/lib/filter/sfCacheFilter.class.php の119行目あたり <?php 117 if ($lifetime = $this->cacheManager->getClientLifeTime($uri, 'page')) 118 { 119 $this->response->setHttpHeader('Last-Modified', $this->response->getDate(time()), false); 120 $this->response->setHttpHeader('Expires', $this->response->getDate(time() + $lifetime), false); 121 $this->response->addCacheControlHttpHeader('max-age', $lifetime); 122