diff --git a/roles/mail/templates/postfix-out/main.cf b/roles/mail/templates/postfix-out/main.cf
index 345a03bb6e19615a195af10f233fe08c4ad3219c..2f1fef651c62f436ce2a874dfacc661121978497 100644
--- a/roles/mail/templates/postfix-out/main.cf
+++ b/roles/mail/templates/postfix-out/main.cf
@@ -55,9 +55,9 @@ virtual_alias_maps = ${indexed}virtual ${ldap}aliases
 # Concurrency tuning for "relay" and "smtp" transport.
 relay_destination_concurrency_limit = 20
 default_destination_concurrency_limit = 20
-smtp_lowpri_destination_recipient_limit = 1
-smtp_lowpri_destination_concurrency_limit = 2
-smtp_lowpri_destination_rate_delay = 2s
+smtp-lowpri_destination_recipient_limit = 1
+smtp-lowpri_destination_concurrency_limit = 2
+smtp-lowpri_destination_rate_delay = 2s
 
 # SSL configuration (outbound).
 smtp_tls_security_level = may