diff --git a/manifests/relay.pp b/manifests/relay.pp
index 27a3c0e..9d1c23c 100644
--- a/manifests/relay.pp
+++ b/manifests/relay.pp
@@ -20,6 +20,8 @@
   $smtp_tls_note_starttls_offer = undef,
   $smtp_tls_security_level = undef,
   $smtp_use_tls = undef,
+  $inet_interfaces = 'loopback-only',
+  $inet_protocols  = 'all',
 ) {
   include postfix
 
@@ -53,5 +55,7 @@
 
   postfix::config::maincfhelper { 'masquerade_domains': value => $masquerade_domains, }
 
-  postfix::config::maincfhelper { 'inet_interfaces': value => 'loopback-only', }
+  postfix::config::maincfhelper { 'inet_interfaces': value => $inet_interfaces, }
+
+  postfix::config::maincfhelper { 'inet_protocols': value => $inet_protocols, }
 }