diff --git a/Trustly/Api/api.php b/Trustly/Api/api.php
index c9fee7d..09e0160 100644
--- a/Trustly/Api/api.php
+++ b/Trustly/Api/api.php
@@ -295,13 +295,13 @@ public function post($url=NULL, $postdata=NULL) {
 		curl_setopt($curl, CURLOPT_PORT, $this->api_port);
 
 		if($this->api_is_https) {
-			if(@CURLOPT_PROTOCOLS != 'CURLOPT_PROTOCOLS') {
+			if(defined('CURLOPT_PROTOCOLS')) {
 				curl_setopt($curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTPS);
 			}
 			curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 2);
 			curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, TRUE);
 		} else {
-			if(@CURLOPT_PROTOCOLS != 'CURLOPT_PROTOCOLS') {
+			if(defined('CURLOPT_PROTOCOLS')) {
 				curl_setopt($curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTP);
 			}
 		}