2 opensource content management systems that rely on Zend Framework. while it's now hard to compete with the amount of features natively available in big players like wordpress, joomla or drupal, a good web site developer should stay informed as various project come online.
Zoolu and Pimcore both rely on Zend Framework, which makes them not simple to install, especially Zoolu whose requirement list is very long. But at that price you get full lucene support, the very powerful search engine supported by the zend framework. Pimcore is not easy to install either but promises to be a full rapid development framework.