diff --git a/module/bug/control.php b/module/bug/control.php
index 6245d24d50..7fc8b04790 100644
--- a/module/bug/control.php
+++ b/module/bug/control.php
@@ -187,6 +187,7 @@ class bug extends control
             if($bug->story)  $storyIdList[$bug->story] = $bug->story;
             if($bug->task)   $taskIdList[$bug->task]   = $bug->task;
             if($bug->toTask) $taskIdList[$bug->toTask] = $bug->toTask;
+            if($bug->activatedDate == '0000-00-00 00:00:00') $bug->activatedDate = 'null';
         }
         $storyList = $storyIdList ? $this->loadModel('story')->getByList($storyIdList) : array();
         $taskList  = $taskIdList  ? $this->loadModel('task')->getByList($taskIdList)   : array();