Hi,
It seem the reason from your hosting, I’ve follow this post: http://stackoverflow.com/questions/10449315/fatal-errorclass-mage-adminhtml-controller-action-not-found-in-bookmarkscontr#answer-10449831 and your site work well now
Your extended class name is misspelled – Mage_Adminhtml_Controller_action should be Mage_Adminhtml_Controller_Action.
Thanks!
