Erreur sur le script

Message:Invalid controller specified (a)

#0 /var/www/www.magninsports.com/library/Zend/Controller/Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http)) #1 /var/www/www.magninsports.com/library/Zend/Application/Bootstrap/Bootstrap.php(105): Zend_Controller_Front->dispatch() #2 /var/www/www.magninsports.com/library/Zend/Application.php(384): Zend_Application_Bootstrap_Bootstrap->run() #3 /var/www/www.magninsports.com/www/index.php(205): Zend_Application->run() #4 {main}

array(3) { ["controller"]=> string(1) "a" ["action"]=> string(5) "index" ["module"]=> string(7) "default" }

Router : default