diff --git a/docker-compose.yml b/docker-compose.yml
index e09ed8c..67cab0e 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -95,7 +95,6 @@ services:
     environment:
       MYSQL_WEBDB_HOSTNAME: db
       MYSQL_WEBDB_DATABASE: cacert
-      CSR_DIRECTORY: /srv/certs/csr
       CRT_DIRECTORY: /srv/certs/crt
       CRL_DIRECTORY: /srv/certs/crl
       SMTP_HOST: smtp
diff --git a/signer_client.Dockerfile b/signer_client.Dockerfile
index 663cd69..577c018 100644
--- a/signer_client.Dockerfile
+++ b/signer_client.Dockerfile
@@ -11,6 +11,7 @@ RUN apt-get update \
     libdbd-mysql-perl \
     libdbi-perl \
     libdevice-serialport-perl \
+    libemail-mime-perl \
     libfile-counterfile-perl \
     libreadonly-perl \
     openssl \