In the file Zend/Controller/Request/Http.php , the function setRequestUri make a clean URI to give it to the dispatcher. With the lines : if (isset($_SERVER['HTTP_HOST']) && strstr($requestUri, $_SERVER['HTTP_HOST'])) { $requestUri = preg_replace('#^[^:]*://[^/]*/#', '/', $requestUri); } the domain name disappears if it appears among the $_SERVER['REQUEST_URI']. But, for example, apache doesn't put the requested domain in the REQUEST_URI, only the part after the first "/".

If you have the same domain name in the GET parameter and so in the REQUEST_URI, it causes a bad cleaning and Zend doesn't find any matching controller. So if you try to get http://mydomain.com//… , it tries to find the controller "&var2=foo".