diff --git a/test/docker_mail/templates/docker-compose.yml b/test/docker_mail/templates/docker-compose.yml
index 85dcd603448845c551d76737934ee90ad1cfaf59..a223165f4ac666584c9c14f55390e663e0244be7 100644
--- a/test/docker_mail/templates/docker-compose.yml
+++ b/test/docker_mail/templates/docker-compose.yml
@@ -34,13 +34,13 @@ services:
       options:
         tag: mailu-front
     ports:
-      - "{{ ext_ip4 }}:25:25"
-      - "{{ ext_ip4 }}:465:465"
-      - "{{ ext_ip4 }}:587:587"
-      - "{{ ext_ip4 }}:110:110"
-      - "{{ ext_ip4 }}:995:995"
-      - "{{ ext_ip4 }}:143:143"
-      - "{{ ext_ip4 }}:993:993"
+      - "25:25"
+      - "465:465"
+      - "587:587"
+      - "110:110"
+      - "995:995"
+      - "143:143"
+      - "993:993"
     labels:
       - "traefik.enable=true"
       - "traefik.http.routers.{{ servicename }}.entrypoints=websecure"
@@ -220,9 +220,12 @@ services:
 networks:
   default:
     driver: bridge
+    enable_ipv6: true
     ipam:
       driver: default
       config:
+        # must be a ULA range
+        - subnet: fd00:dead:beef:25::/64
         - subnet: 192.168.203.0/24
   noinet:
     driver: bridge