clamd/Dockerfile

-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \

dovecot/Dockerfile

-FROM buildpack-deps:bullseye as delete_to_trash
+FROM docker.io/buildpack-deps:bullseye as delete_to_trash
 # hadolint ignore=DL3008,DL3015
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive  apt-get install -y dovecot-dev && \
     git clone https://github.com/pali/dovecot_deleted_to_trash && \
     make -C dovecot_deleted_to_trash
 
-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \

exim4/Dockerfile

-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008,DL4006
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
@@ -19,6 +19,7 @@ RUN apt-get update && \
     install -d -o Debian-exim -g Debian-exim -m 755 /var/lib/exim4/ && \
     install -o root -g ssl-cert -m 664 /dev/null /etc/ssl/certs/ssl-cert-snakeoil.pem && \
     install -o root -g ssl-cert -m 664 /dev/null /etc/ssl/private/ssl-cert-snakeoil.key && \
+    install -o root -g root -m 755 /usr/share/exim4 && \
     install -o root -g ssl-cert -m 664 /dev/null /usr/share/exim4/dh.pem && \
     setcap CAP_NET_BIND_SERVICE=+ep /usr/sbin/exim4 && \
     rm -rf /usr/share/exim4/dh.pem /var/lib/exim4/config.autogenerated /etc/exim4/* && \

spamd/Dockerfile

-FROM debian:bullseye-slim
+FROM docker.io/debian:bullseye-slim
 # hadolint ignore=DL3008
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \