diff --git a/Dockerfile b/Dockerfile
index 87d9fce1..61433623 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -9,7 +9,7 @@ ENV ONE_DIR=0
 RUN apt-get update -q --fix-missing && \
   apt-get -y upgrade && \
   apt-get -y install postfix
-RUN DEBIAN_FRONTEND=noninteractive apt-get update -q --fix-missing && \
+RUN apt-get update -q --fix-missing && \
   apt-get -y upgrade && \
   apt-get -y install --no-install-recommends \
     amavisd-new \
@@ -33,6 +33,7 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update -q --fix-missing && \
     gamin \
     gzip \
     iptables \
+    locales \
     libmail-spf-perl \
     libnet-dns-perl \
     libsasl2-modules \
diff --git a/Makefile b/Makefile
index cccb1c89..e380f5d9 100644
--- a/Makefile
+++ b/Makefile
@@ -56,7 +56,7 @@ run:
 		-v "`pwd`/test":/tmp/docker-mailserver-test \
 		-e PERMIT_DOCKER=network \
 		-e OVERRIDE_HOSTNAME=mail.my-domain.com \
-		-h unknown.domain.tld \
+		-h mail.my-domain.com \
 		-t $(NAME)
 	sleep 15
 	docker run -d --name mail_fail2ban \
diff --git a/test/tests.bats b/test/tests.bats
index 3e7c1013..6396a6b4 100644
--- a/test/tests.bats
+++ b/test/tests.bats
@@ -15,7 +15,7 @@ load 'test_helper/bats-assert/load'
 }
 
 @test "checking configuration: hostname/domainname override: check container hostname is applied correctly" {
-  run docker exec mail_override_hostname /bin/bash -c "hostname | grep unknown.domain.tld"
+  run docker exec mail_override_hostname /bin/bash -c "hostname | grep mail.my-domain.com"
   assert_success
 }