diff --git a/Dockerfile b/Dockerfile
index b256bca..081f6a4 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -70,11 +70,6 @@ ENV HOME /home/$USER
 RUN useradd -u $UID -m -d $HOME -s /usr/sbin/nologin $USER \
     && usermod -aG $GROUPS $USER
 
-# for some unknown reason the ownCloud's (v9.0.0) calendar (v1.0.0.0) doesn't
-# show up the calendars when the time is set to UTC/Zulu
-RUN echo "UTC" > /etc/timezone \
-    && dpkg-reconfigure tzdata
-
 WORKDIR $HOME
 USER $USER
 
diff --git a/docker-compose.yml b/docker-compose.yml
index fd44d87..7383ffa 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -15,6 +15,7 @@ services:
       - /usr/share/icons:/usr/share/icons:ro
       - /var/run/cups:/var/run/cups:ro
       # - /tmp/krb5cc_1000:/tmp/krb5cc_1000:ro
+      - /etc/localtime:/etc/localtime:ro
       - /etc/machine-id:/etc/machine-id:ro
       - /run/user/1000/pulse:/run/user/1000/pulse
       - $HOME/.mozilla:/home/firefox/.mozilla