diff --git a/interface/web/admin/form/firewall.tform.php b/interface/web/admin/form/firewall.tform.php
index 7c5a29b016023a26a5a88fd4492300a96ac654ef..eb7dcb3acf83bf7d603d7a3454fe62b2610b2ee9 100644
--- a/interface/web/admin/form/firewall.tform.php
+++ b/interface/web/admin/form/firewall.tform.php
@@ -76,7 +76,7 @@ $form["tabs"]['firewall'] = array (
 			'datatype' => 'VARCHAR',
 			'formtype' => 'TEXT',
 			'validators' => array (  0 => array ( 'type' => 'REGEX',
-					'regex' => '/^\d{1,5}(?::\d{1,5})?(?:,\d{1,5}(?::\d{1,5})?)*$/',
+					'regex' => '/^$|\d{1,5}(?::\d{1,5})?(?:,\d{1,5}(?::\d{1,5})?)*$/',
 					'errmsg'=> 'tcp_ports_error_regex'),
 			),
 			'default' => '20,21,22,25,53,80,110,143,443,465,587,993,995,3306,8080,8081,10000',
@@ -88,7 +88,7 @@ $form["tabs"]['firewall'] = array (
 			'datatype' => 'VARCHAR',
 			'formtype' => 'TEXT',
 			'validators' => array (  0 => array ( 'type' => 'REGEX',
-					'regex' => '/^\d{1,5}(?::\d{1,5})?(?:,\d{1,5}(?::\d{1,5})?)*$/',
+					'regex' => '/^$|\d{1,5}(?::\d{1,5})?(?:,\d{1,5}(?::\d{1,5})?)*$/',
 					'errmsg'=> 'udp_ports_error_regex'),
 			),
 			'default' => '53,3306',