diff --git a/htdocs/core/class/smtps.class.php b/htdocs/core/class/smtps.class.php
index dc58c54f122..81b90e9ce89 100644
--- a/htdocs/core/class/smtps.class.php
+++ b/htdocs/core/class/smtps.class.php
@@ -102,7 +102,7 @@ class SMTPs
 	 *
 	 * @var	array	$_msgContent	Array of messages
 	 */
-	private array $_msgContent = array();
+	private $_msgContent = array();
 
 	/**
 	 * Custom X-Headers