diff --git a/exim.conf b/exim.conf
index 18fb50b..12e9550 100644
--- a/exim.conf
+++ b/exim.conf
@@ -1,5 +1,7 @@
 domainlist forward_domains = lsearch;/etc/exim/db/forward_domains
 
+primary_hostname = mx.hottis.de
+
 tls_advertise_hosts = *
 tls_certificate = /etc/exim/ssl/server.crt
 tls_privatekey = /etc/exim/ssl/server.key