diff --git a/lib/classes/task/adhoc_task.php b/lib/classes/task/adhoc_task.php
index 916b92b31ea..91b55c61f48 100644
--- a/lib/classes/task/adhoc_task.php
+++ b/lib/classes/task/adhoc_task.php
@@ -64,6 +64,14 @@ abstract class adhoc_task extends task_base {
         $this->customdata = json_encode($customdata);
     }
 
+    /**
+     * Alternate setter for $customdata. Expects the data as a json_encoded string.
+     * @param string json_encoded string
+     */
+    public function set_custom_data_as_string($customdata) {
+        $this->customdata = $customdata;
+    }
+
     /**
      * Getter for $customdata.
      * @return mixed (anything that can be handled by json_decode).
@@ -72,4 +80,13 @@ abstract class adhoc_task extends task_base {
         return json_decode($this->customdata);
     }
 
+    /**
+     * Alternate getter for $customdata.
+     * @return string (this is the raw json encoded version).
+     */
+    public function get_custom_data_as_string() {
+        return $this->customdata;
+    }
+
+
 }
diff --git a/lib/classes/task/manager.php b/lib/classes/task/manager.php
index be60ee2a9a1..e2ec497a3fb 100644
--- a/lib/classes/task/manager.php
+++ b/lib/classes/task/manager.php
@@ -220,7 +220,7 @@ class manager {
         $record->blocking = $task->is_blocking();
         $record->nextruntime = $task->get_next_run_time();
         $record->faildelay = $task->get_fail_delay();
-        $record->customdata = $task->get_custom_data();
+        $record->customdata = $task->get_custom_data_as_string();
 
         return $record;
     }
@@ -254,7 +254,7 @@ class manager {
             $task->set_fail_delay($record->faildelay);
         }
         if (isset($record->customdata)) {
-            $task->set_custom_data($record->customdata);
+            $task->set_custom_data_as_string($record->customdata);
         }
 
         return $task;