diff --git a/src/www/firewall_nat_out_edit.php b/src/www/firewall_nat_out_edit.php
index 933742106..882874119 100644
--- a/src/www/firewall_nat_out_edit.php
+++ b/src/www/firewall_nat_out_edit.php
@@ -46,7 +46,7 @@ function formTranslateAddresses() {
     // add VIPs's
     if (isset($config['virtualip']['vip'])) {
         foreach ($config['virtualip']['vip'] as $sn) {
-            if (!isset($sn['noexpand'])) {
+            if (empty($sn['noexpand'])) {
                 if ($sn['mode'] == "proxyarp") {
                     $start = ip2long32(gen_subnet($sn['subnet'], $sn['subnet_bits']));
                     $end = ip2long32(gen_subnet_max($sn['subnet'], $sn['subnet_bits']));