CURLCLOSEPOLICY_LEAST_RECENTLY_USED not defined anymore in PHP 5.6.4: is it better to replace with something else or to comment out the reference?

I’ve just moved my PHP application (WooCommerce above WordPress) to a server using PHP 5.6.4 and I get this warning:

Warning: curl_setopt() expects parameter 2 to be long, string given in /srv/users/serverpilot/apps/wordpress/public/wp-content/plugins/woocommerce-amazon-s3-storage/amazon_sdk/lib/requestcore/requestcore.class.php on line 610

As far as I can see, it happens when I’m trying to reference to this built-in var CURLCLOSEPOLICY_LEAST_RECENTLY_USED which is not defined anymore on PHP 5.6

Is it better to replace with CURLCLOSEPOLICY_OLDEST or to comment out the curl_setopt($handle, CURLOPT_CLOSEPOLICY, CURLCLOSEPOLICY_LEAST_RECENTLY_USED) set?