diff --git a/docker-compose.yml b/docker-compose.yml
index 6d07260e0c78c48663de1db6c7417353b70cb6fa..a870ab9d30758a88271fe1444bec2038af9896ae 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -30,7 +30,7 @@ services:
       TRUSTED_PROXY:
       REMOTES:
     networks:
-      - postfix
+      - postfix-test
       - default
 
   postfix:
@@ -45,7 +45,7 @@ services:
       - "./log/postfix:/var/log/postfix"
       - "spool_postfix:/var/spool/postfix"
     networks:
-      - postfix
+      - postfix-test
     environment:
       POSTFIX_VIRTUAL_DOMAINS:
       MAILNAME:
@@ -79,7 +79,7 @@ volumes:
   lib_sympa:
 
 networks:
-  postfix:
+  postfix-test:
     ipam:
       config:
-        - subnet: 10.42.0.0/16
+        - subnet: 10.45.0.0/16
diff --git a/docker/postfix/etc/postfix/sasl/smtpd.conf b/docker/postfix/etc/postfix/sasl/smtpd.conf
new file mode 100644
index 0000000000000000000000000000000000000000..18d730882b66f8011430d4890882b5a017a504f5
--- /dev/null
+++ b/docker/postfix/etc/postfix/sasl/smtpd.conf
@@ -0,0 +1,2 @@
+pwcheck_method: saslauthd
+mech_list: plain login
diff --git a/shared.yml b/shared.yml
index e665647e67dfbfa7181237b29e426517917393a2..69d20729503f90b0002baf332e278821f8317c70 100644
--- a/shared.yml
+++ b/shared.yml
@@ -4,7 +4,7 @@ services:
   sympa:
     networks:
       - default
-      - postfix
+      - postfix-test
       - dolibarr_shared
 
 networks: