setConnection example

        // If sending multiple messages per session use existing adapter         if (!($this->_connection instanceof Zend_Mail_Protocol_Smtp)) {
            // Check if authentication is required and determine required class             $connectionClass = 'Zend_Mail_Protocol_Smtp';
            if ($this->_auth) {
                $connectionClass .= '_Auth_' . ucwords($this->_auth);
            }
            if (!class_exists($connectionClass)) {
                Zend_Loader::loadClass($connectionClass);
            }
            $this->setConnection(new $connectionClass($this->_host, $this->_port, $this->_config));
            $this->_connection->connect();
            $this->_connection->helo($this->_name);
        } else {
            // Reset connection to ensure reliable transaction             $this->_connection->rset();
        }

        // Set sender email address         $this->_connection->mail($this->_mail->getReturnPath());

        // Set recipient forward paths