diff --git a/clients/gplan.inc b/clients/gplan.inc
index 9c87238..a5dc1de 100644
--- a/clients/gplan.inc
+++ b/clients/gplan.inc
@@ -31,7 +31,7 @@ class AppointmentsGPlanClient extends AppointmentsClientApi {
     // This triggers Exceptions by soap client.
     $options['exceptions'] = TRUE;
 
-    drupal_alter('dvg_appointment_soap_options', $options);
+    drupal_alter('dvg_appointments_soap_options', $options);
 
     try {
       $this->soap_client = new SoapClient($this->url, $options);
diff --git a/clients/gplan_multiple.inc b/clients/gplan_multiple.inc
index 7c0bfca..d779473 100644
--- a/clients/gplan_multiple.inc
+++ b/clients/gplan_multiple.inc
@@ -31,7 +31,7 @@ class AppointmentsGPlanMultipleClient extends AppointmentsClientApi {
     // This triggers Exceptions by soap client.
     $options['exceptions'] = TRUE;
 
-    drupal_alter('dvg_appointment_soap_options', $options);
+    drupal_alter('dvg_appointments_soap_options', $options);
 
     try {
       $this->soap_client = new SoapClient($this->url, $options);
diff --git a/dvg_appointments.api.php b/dvg_appointments.api.php
index 521ee77..c06a326 100644
--- a/dvg_appointments.api.php
+++ b/dvg_appointments.api.php
@@ -113,6 +113,51 @@ function hook_dvg_appointments_available_products_alter(&$available_products, $e
   }
 }
 
+/**
+ * Alter the options used for the SoapClient.
+ * E.g. add 2 way SSL.
+ *
+ * @param array $options
+ *   Options that are passed to the SoapClient.
+ */
+function hook_dvg_appointments_soap_options_alter(&$options) {
+  $opts = array(
+    'ssl' => array(
+      'verify_peer' => FALSE,
+      'verify_peer_name' => FALSE,
+      'local_cert' => '/path/to/my/fancy/cert',
+      'passphrase' => 'wow so_s3cRet!',
+    ),
+  );
+  $options['local_cert'] = $opts['ssl']['local_cert'];
+  $options['passphrase'] = $opts['ssl']['passphrase'];
+  $options['stream_context'] = stream_context_create($opts);
+}
+
+/**
+ * Alter the options used for the drupal_http_request.
+ * E.g. add 2 way SSL.
+ *
+ * @param array  $options
+ *   Options that are passed to the drupal_http_request function.
+ * @param string $function
+ *   Function the REST API is calling.
+ * @param string $rest_url
+ *   REST URL that will be called.
+ */
+function hook_dvg_appointments_rest_options_alter(&$options, $function, $rest_url) {
+  // See available options: https://secure.php.net/manual/en/context.ssl.php
+  $opts = array(
+    'ssl' => array(
+      'verify_peer' => FALSE,
+      'verify_peer_name' => FALSE,
+      'local_cert' => '/path/to/my/fancy/cert',
+      'passphrase' => 'wow so_s3cRet!',
+    ),
+  );
+  $options['context'] = stream_context_create($opts);
+}
+
 /**
  * @} End of "addtogroup hooks".
  */
diff --git a/dvg_appointments.client.inc b/dvg_appointments.client.inc
index 7691f68..4a092b8 100644
--- a/dvg_appointments.client.inc
+++ b/dvg_appointments.client.inc
@@ -41,6 +41,7 @@ abstract class AppointmentsClientApi {
         );
 
         $options = $this->get_options($args, $method);
+        drupal_alter('dvg_appointments_rest_options', $options, $function, $rest_url);
         $response = drupal_http_request(url($rest_url, array('query' => $rest_url_parameters)), $options);
         $return = json_decode($response->data);
         if (isset($response->code) && isset($response->error)) {