diff --git a/deb/Dockerfile b/deb/Dockerfile
index a0d8e2c..efdbcbf 100644
--- a/deb/Dockerfile
+++ b/deb/Dockerfile
@@ -12,8 +12,8 @@ RUN bash /install.sh
 FROM debian:sid-slim
 LABEL maintainer="Simon Felding <sife@adm.ku.dk>"
 
-EXPOSE 25/tcp
-EXPOSE 143/tcp
+EXPOSE 12025/tcp
+EXPOSE 12143/tcp
 
 WORKDIR /protonmail