diff --git a/security/acme-client/Makefile b/security/acme-client/Makefile
index 1b4b91a18..bf0523622 100644
--- a/security/acme-client/Makefile
+++ b/security/acme-client/Makefile
@@ -1,6 +1,5 @@
 PLUGIN_NAME=		acme-client
-PLUGIN_VERSION=		1.17
-PLUGIN_REVISION=	1
+PLUGIN_VERSION=		1.18
 PLUGIN_COMMENT=		Let's Encrypt client
 PLUGIN_MAINTAINER=	opnsense@moov.de
 PLUGIN_DEPENDS=		acme.sh bind912
diff --git a/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/Api/SettingsController.php b/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/Api/SettingsController.php
index 3a7fdf7e1..3771b6b7e 100644
--- a/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/Api/SettingsController.php
+++ b/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/Api/SettingsController.php
@@ -309,7 +309,7 @@ class SettingsController extends ApiMutableModelControllerBase
                 }
 
                 // Ensure HAProxy frontend additions have been applied.
-                foreach ($mdlAcme->getNodeByReference('validations.validation')->__items as $validation) {
+                foreach ($mdlAcme->getNodeByReference('validations.validation')->iterateItems() as $validation) {
                     // Find all (enabled) validation methods with HAProxy integration.
                     if ((string)$validation->enabled == "1" and
                         (string)$validation->method == "http01" and
diff --git a/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml b/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml
index e07d394ca..4aa5dc036 100644
--- a/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml
+++ b/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml
@@ -750,4 +750,45 @@
         <label>API Key</label>
         <type>text</type>
     </field>
+    <field>
+        <label>GratisDNS.dk</label>
+        <type>header</type>
+        <style>table_dns table_dns_gdnsdk</style>
+    </field>
+    <field>
+        <id>validation.dns_gdnsdk_user</id>
+        <label>User</label>
+        <type>text</type>
+    </field>
+    <field>
+        <id>validation.dns_gdnsdk_password</id>
+        <label>Password</label>
+        <type>password</type>
+    </field>
+    <field>
+        <label>ACME DNS</label>
+        <type>header</type>
+        <style>table_dns table_dns_acmedns</style>
+	</field>
+    <field>
+        <id>validation.dns_acmedns_user</id>
+        <label>User</label>
+        <type>text</type>
+    </field>
+    <field>
+        <id>validation.dns_acmedns_password</id>
+        <label>Password</label>
+        <type>password</type>
+    </field>
+    <field>
+        <id>validation.dns_acmedns_subdomain</id>
+        <label>Subdomain</label>
+        <type>text</type>
+    </field>
+    <field>
+        <id>validation.dns_acmedns_updateurl</id>
+        <label>Update URL</label>
+        <type>text</type>
+        <help>Specify the custom ACME DNS Update URL, i.e. https://auth.acme-dns.io/update (optional)</help>
+    </field>
 </form>
diff --git a/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.php b/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.php
index 70427ab5c..6c19ca79f 100644
--- a/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.php
+++ b/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.php
@@ -45,7 +45,7 @@ class AcmeClient extends BaseModel
      */
     public function getByCertificateID($certificateid)
     {
-        foreach ($this->certificates->certificate->__items as $certificate) {
+        foreach ($this->certificates->certificate->iterateItems() as $certificate) {
             if ((string)$certificateid === (string)$certificate->certificateid) {
                 return $certificate;
             }
@@ -62,7 +62,7 @@ class AcmeClient extends BaseModel
     {
         if ((string)$this->settings->enabled === "1") {
             if ($checkCertificates === true) {
-                foreach ($this->certificates->certificate->__items as $certificate) {
+                foreach ($this->certificates->certificate->iterateItems() as $certificate) {
                     if ((string)$certificate->enabled == "1") {
                         return true; // Found a active certificate
                     }
@@ -81,7 +81,7 @@ class AcmeClient extends BaseModel
      */
     public function getByActionID($uuid)
     {
-        foreach ($this->actions->action->__items as $action) {
+        foreach ($this->actions->action->iterateItems() as $action) {
             if ((string)$uuid === (string)$action->getAttributes()["uuid"]) {
                 return $action;
             }
diff --git a/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml b/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml
index f3a6dd373..aa73224eb 100644
--- a/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml
+++ b/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml
@@ -339,6 +339,7 @@
                     <Required>Y</Required>
                     <default>dns_nsupdate</default>
                     <OptionValues>
+                        <dns_acmedns>ACME DNS API</dns_acmedns>
                         <dns_ad>Alwaysdata.com API</dns_ad>
                         <dns_ali>aliyun.com API</dns_ali>
                         <dns_autodns>autoDNS (InternetX) API</dns_autodns>
@@ -361,6 +362,7 @@
                         <dns_freedns>FreeDNS API</dns_freedns>
                         <dns_gandi_livedns>Gandi LiveDNS API</dns_gandi_livedns>
                         <dns_gd>GoDaddy.com API</dns_gd>
+                        <dns_gdnsdk>GratisDNS.dk</dns_gdnsdk>
                         <dns_he>Hurricane Electric</dns_he>
                         <dns_infoblox>Infoblox API</dns_infoblox>
                         <dns_inwx>INWX XMLRPC API</dns_inwx>
@@ -655,6 +657,24 @@
                 <dns_zm_key type="TextField">
                     <Required>N</Required>
                 </dns_zm_key>
+                <dns_gdnsdk_user type="TextField">
+                   <Required>N</Required>
+                </dns_gdnsdk_user>
+                <dns_gdnsdk_password type="TextField">
+                   <Required>N</Required>
+                </dns_gdnsdk_password>
+                <dns_acmedns_user type="TextField">
+                   <Required>N</Required>
+                </dns_acmedns_user>
+                <dns_acmedns_password type="TextField">
+                   <Required>N</Required>
+                </dns_acmedns_password>
+                <dns_acmedns_subdomain type="TextField">
+                   <Required>N</Required>
+                </dns_acmedns_subdomain>
+                <dns_acmedns_updateurl type="TextField">
+                   <Required>N</Required>
+                </dns_acmedns_updateurl>
             </validation>
         </validations>
         <actions>
diff --git a/security/acme-client/src/opnsense/scripts/OPNsense/AcmeClient/certhelper.php b/security/acme-client/src/opnsense/scripts/OPNsense/AcmeClient/certhelper.php
index 56222e8a5..77f0a39e7 100755
--- a/security/acme-client/src/opnsense/scripts/OPNsense/AcmeClient/certhelper.php
+++ b/security/acme-client/src/opnsense/scripts/OPNsense/AcmeClient/certhelper.php
@@ -1,37 +1,33 @@
 #!/usr/local/bin/php
 <?php
 
-/**
- *    Based in parts on certs.inc and system_camanager.php (thus the extended copyright notice).
+/*
+ * Copyright (C) 2017-2018 Frank Wall
+ * Copyright (C) 2015 Deciso B.V.
+ * Copyright (C) 2010 Jim Pingle <jimp@pfsense.org>
+ * Copyright (C) 2008 Shrew Soft Inc. <mgrooms@shrew.net>
+ * All rights reserved.
  *
- *    Copyright (C) 2017-2018 Frank Wall
- *    Copyright (C) 2015 Deciso B.V.
- *    Copyright (C) 2010 Jim Pingle <jimp@pfsense.org>
- *    Copyright (C) 2008 Shrew Soft Inc. <mgrooms@shrew.net>
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
  *
- *    All rights reserved.
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
  *
- *    Redistribution and use in source and binary forms, with or without
- *    modification, are permitted provided that the following conditions are met:
- *
- *    1. Redistributions of source code must retain the above copyright notice,
- *       this list of conditions and the following disclaimer.
- *
- *    2. Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in the
- *       documentation and/or other materials provided with the distribution.
- *
- *    THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
- *    INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
- *    AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- *    AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
- *    OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- *    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- *    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- *    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- *    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- *    POSSIBILITY OF SUCH DAMAGE.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
  *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+ * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
  */
 
 // Hello. I am the spaghetti monster. Yummy.
@@ -42,14 +38,13 @@ require_once("certs.inc");
 require_once("legacy_bindings.inc");
 require_once("interfaces.inc");
 require_once("util.inc");
+
 // Some stuff requires the almighty MVC framework.
 use OPNsense\Core\Backend;
 use OPNsense\Core\Config;
 use OPNsense\Base;
 use OPNsense\AcmeClient\AcmeClient;
 
-global $config;
-global $postponed_updates;
 $postponed_updates = array();
 
 /* CLI arguments:
@@ -145,7 +140,7 @@ function cert_action_validator($opt_cert_id)
                 $acctRef = (string)$certObj->account;
                 $acctObj = null;
                 $acctref_found = false;
-                foreach ($modelObj->getNodeByReference('accounts.account')->__items as $node) {
+                foreach ($modelObj->getNodeByReference('accounts.account')->iterateItems() as $node) {
                     if ((string)$node->getAttributes()["uuid"] == $acctRef) {
                         $acctref_found = true;
                         $acctObj = $node;
@@ -182,7 +177,7 @@ function cert_action_validator($opt_cert_id)
                 $valRef = (string)$certObj->validationMethod;
                 $valObj = null;
                 $ref_found = false;
-                foreach ($modelObj->getNodeByReference('validations.validation')->__items as $node) {
+                foreach ($modelObj->getNodeByReference('validations.validation')->iterateItems() as $node) {
                     if ((string)$node->getAttributes()["uuid"] == $valRef) {
                         $ref_found = true;
                         $valObj = $node;
@@ -782,6 +777,16 @@ function run_acme_validation($certObj, $valObj, $acctObj)
             case 'dns_zonomi':
                 $proc_env['ZM_Key'] = (string)$valObj->dns_zm_key;
                 break;
+            case 'dns_gdnsdk':
+                $proc_env['GDNSDK_Username'] = (string)$valObj->dns_gdnsdk_user;
+                $proc_env['GDNSDK_Password'] = (string)$valObj->dns_gdnsdk_password;
+                break;
+            case 'dns_acmedns':
+                $proc_env['ACMEDNS_USERNAME'] = (string)$valObj->dns_acmedns_user;
+                $proc_env['ACMEDNS_PASSWORD'] = (string)$valObj->dns_acmedns_password;
+                $proc_env['ACMEDNS_SUBDOMAIN'] = (string)$valObj->dns_acmedns_subdomain;
+                $proc_env['ACMEDNS_UPDATE_URL'] = (string)$valObj->dns_acmedns_updateurl;
+                break;
             default:
                 log_error("AcmeClient: invalid DNS-01 service specified: " . (string)$valObj->dns_service);
                 return(1);