diff --git a/charts/mok/Chart.yaml b/charts/mok/Chart.yaml
index 94bf2a5204a70ac1b7c6b23abf99703ac602c295..edf7bddc5ce6c4199b9d87e722ab494d592053f4 100644
--- a/charts/mok/Chart.yaml
+++ b/charts/mok/Chart.yaml
@@ -3,7 +3,7 @@ name: mok
 description: |
   Mail on Kubernetes (MoK) is a project to deploy a functional mailserver that runs without a database server on Kubernetes, taking advantage of configmaps and secret.
 type: application
-version: 0.5.2
+version: 0.6.0
 sources:
   - https://de.postfix.org/ftpmirror/index.html
   - https://github.com/dovecot/core
diff --git a/charts/mok/README.md b/charts/mok/README.md
index 69a685b3cfbc27f04c8cae84463a42e1d947f0e5..6ffc8aba3fa87a309d6041b1bc23606b2396478c 100644
--- a/charts/mok/README.md
+++ b/charts/mok/README.md
@@ -1,6 +1,6 @@
 # mok
 
-![Version: 0.5.2](https://img.shields.io/badge/Version-0.5.2-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square)
+![Version: 0.6.0](https://img.shields.io/badge/Version-0.6.0-informational?style=flat-square) ![Type: application](https://img.shields.io/badge/Type-application-informational?style=flat-square)
 
 Mail on Kubernetes (MoK) is a project to deploy a functional mailserver that runs without a database server on Kubernetes, taking advantage of configmaps and secret.
 
@@ -53,6 +53,7 @@ Mail on Kubernetes (MoK) is a project to deploy a functional mailserver that run
 | nameOverride | string | `""` |  |
 | networkPolicy.create | bool | `true` | Create NetworkPolicies to access the mailserver from outside |
 | postfix.affinity | object | `{}` |  |
+| postfix.hostname | string | `nil` | explicitly set postfix hostname |
 | postfix.image.pullPolicy | string | `"IfNotPresent"` |  |
 | postfix.image.repository | string | `"quay.io/shivering-isles/postfix"` | postfix container image |
 | postfix.image.tag | string | `"0.2.3"` | Overrides the image tag whose default is "latest" |
diff --git a/charts/mok/templates/postfix.yaml b/charts/mok/templates/postfix.yaml
index 6a3e32405d98a6ab9aff4bb9cbb901fef0c70335..ab3b7ae5b70d1910f9304e8ee62a7f4e182af847 100644
--- a/charts/mok/templates/postfix.yaml
+++ b/charts/mok/templates/postfix.yaml
@@ -75,6 +75,10 @@ spec:
           env:
             - name: DOVECOT_SERVICE_NAME
               value: {{ include "mok.fullname" . }}-dovecot-internal.{{ .Release.Namespace }}.svc.cluster.local
+            {{- if .Values.postfix.hostname }}
+            - name: HOSTNAME
+              value: {{ .Values.postfix.hostname }}
+            {{- end }}
           image: {{ .Values.postfix.image.repository }}:{{.Values.postfix.image.tag | default "latest" }}
           imagePullPolicy: {{ .Values.postfix.image.pullPolicy }}
           lifecycle:
diff --git a/charts/mok/values.yaml b/charts/mok/values.yaml
index 816aa2e3b5d85cec0c54784692852b34ad0a0380..58fd3b8119268fdbe1611d0953e150df20d0ae61 100644
--- a/charts/mok/values.yaml
+++ b/charts/mok/values.yaml
@@ -36,6 +36,8 @@ relay:
 
 
 postfix:
+  # -- explicitly set postfix hostname
+  hostname: null
   # -- Number of postfix pods.
   replicaCount: 1