Zend_Http_Client builds a request path string like following code. http://framework.zend.com/developer/browser/trunk/library/Zend/Http/Client.php#L74 74 $request = array_merge(array('GET ' . $this->_uri->getPath() . '?' . $this->_uri->getQuery() . ' HTTP/1.0', This code always makes a path string with "?" if URL has no querystring. ex) "/path/to/file?" But some webpages return other contents if the path string has "?" or not. ex) http://wordpress.rauru-block.org/index.php/1354 and http://wordpress.rauru-block.org/index.php/1354? So please change like this. 74 $request = array_merge(array('GET ' . $this->_uri->getPath() . (($this->_uri->getQuery() !== false) ? '?' . $this->_uri->getQuery() : '') . ' HTTP/1.0',