diff --git a/create_master_zone_file.sh b/create_master_zone_file.sh
index 978cd77..72bb769 100755
--- a/create_master_zone_file.sh
+++ b/create_master_zone_file.sh
@@ -671,6 +671,19 @@ else
 
 fi
 
+_NS_DOMAIN="$(get_domain_by_hostname "${MX_HOST_1}")"
+SOA_HOST_NAME=""
+
+if [[ "${_NS_DOMAIN}" = "oopen.de" ]] ; then
+   SOA_HOST_NAME="domreg.${_NS_DOMAIN}"
+elif [[ "${_NS_DOMAIN}" = "warenform.de" ]] ; then
+   SOA_HOST_NAME="admin.${_NS_DOMAIN}"
+elif [[ "${_NS_DOMAIN}" = "so36net.de" ]] ; then
+   SOA_HOST_NAME="root.${_NS_DOMAIN}"
+else
+   SOA_HOST_NAME="postmaster.${_NS_DOMAIN}"
+fi
+
 blank_line
 
 echononl "   Backup directory '${ZONE_FILE_MASTER_DIR}'.."
@@ -691,7 +704,7 @@ cat << EOF > "${ZONE_FILE_MASTER_DIR}/${DOMAIN}.zone"
 ; - domain: ${DOMAIN}
 ; -
 \$TTL 43200
-@ 86400 IN SOA ${NS_HOST_1}. admin.$(get_domain_by_hostname "${NS_HOST_1}"). (
+@ 86400 IN SOA ${NS_HOST_1}. ${SOA_HOST_NAME}. (
                     $(date +%Y%m%d01)  ; serial
                     14400       ; refresh
                     3600        ; retry