diff --git a/Dockerfile b/Dockerfile
index 3909755..b7584da 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,7 +2,7 @@ FROM ubuntu:16.04
 
 MAINTAINER Julien Fastré <julienfastre@cvfe.be>
 
-ARG version=3.2.5
+ARG version=3.2.6a
 
 WORKDIR /tmp/build
 
diff --git a/README.md b/README.md
index 74ff7cc..62fe635 100644
--- a/README.md
+++ b/README.md
@@ -108,6 +108,10 @@ The assets (css, js, ...) are contained in a volume. Those assets are completely
 - remove the volume containing those assets, to let a clean place for the asset for the new version.
 - or use an anonymous volume, which will be re-created on each restart
 
+## Usage of sendmail / `SOGoMailingMechanism`
+
+Sendmail is not installed in this image: sogo must be able to send mails using a smtp server. The `sogo.conf` file must have the option `SOGoMailingMechanism` on `smtp`. See [the section "SMTP Server Configuration" of the sogo manual](https://sogo.nu/files/docs/SOGo%20Installation%20Guide.pdf#33).
+
 ## Bug report
 
 Please reports bug on https://github.com/julienfastre/docker-sogo/issues
diff --git a/docker-compose.yml b/docker-compose.yml
index 5b45724..e8a9df3 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -8,7 +8,7 @@ services:
       build: 
          context: .
          args:
-            - version=3.2.5
+            - version=3.2.6a
 
 #     if you want to use builded image, uncomment next line
 #      image: julienfastre/sogo:3.2