Fatal error: Uncaught Error: Undefined constant "Sabre\HTTP\CURLOPT_RETURNTRANSFER" in /users/forscher/www/Baikal/vendor/sabre/http/lib/Client.php:81 Stack trace: #0 /users/forscher/www/Baikal/vendor/sabre/http/examples/client.php(31): Sabre\HTTP\Client->__construct() #1 {main} thrown in /users/forscher/www/Baikal/vendor/sabre/http/lib/Client.php on line 81