diff --git a/files/10-auth.conf.tmpl b/files/10-auth.conf.tmpl
index 9ded33b..7838f82 100644
--- a/files/10-auth.conf.tmpl
+++ b/files/10-auth.conf.tmpl
@@ -1,5 +1,5 @@
 auth_realms = {{ getv "/mail/domains" }}
-auth_default_realm = {{ index (split (getv "/mail/domains") " ") 1 }}
+auth_default_realm = {{ index (split (getv "/mail/domains") " ") 0 }}
 auth_username_format = {{ getv "/auth/username/format" }}
 auth_mechanisms = {{ getv "/auth/mechanisms" }}
 
diff --git a/files/20-lmtp.conf.tmpl b/files/20-lmtp.conf.tmpl
index 4e5b419..529db27 100644
--- a/files/20-lmtp.conf.tmpl
+++ b/files/20-lmtp.conf.tmpl
@@ -1,5 +1,5 @@
 protocol lmtp {
   # postmaster_address aparentemente es obligatorio
-  postmaster_address = postmaster@{{ index (split (getv "/mail/domains") " ") 1 }}
+  postmaster_address = postmaster@{{ index (split (getv "/mail/domains") " ") 0 }}
   mail_plugins = $mail_plugins sieve
 }