diff --git a/includes/services/check_smtp.inc.php b/includes/services/check_smtp.inc.php
index c3af27bd7f..5c3807a693 100644
--- a/includes/services/check_smtp.inc.php
+++ b/includes/services/check_smtp.inc.php
@@ -1,2 +1,2 @@
 <?php
-$check_cmd = $config['nagios_plugins'] . "/check_smtp -H ".$service['hostname'];
+$check_cmd = $config['nagios_plugins'] . "/check_smtp -H ".$service['hostname']." ".$service['service_param'];