diff --git a/firewall/manifests/init.pp b/firewall/manifests/init.pp
index 1cbbbcb..d2da3d0 100644
--- a/firewall/manifests/init.pp
+++ b/firewall/manifests/init.pp
@@ -216,7 +216,7 @@ class firewall::common::iptables {
     if $firewall_modules {
         case $::operatingsystem {
             "centos","fedora","redhat": {
-                $firewall_modules_str = inline_template('<%= @firewall_modules.join(" ") -%>')
+                $firewall_modules_str = inline_template('"<%= @firewall_modules.join(" ") -%>"')
                 augeas { "iptables-config":
                     context => "/files/etc/sysconfig/iptables-config",
                     changes => [ "set IPTABLES_MODULES '${firewall_modules_str}'" ],