Zend certified PHP/Magento developer

No mapping found for [added_on_value.sort_added_on] in order to sort on

I am trying to create new product attribute of type datetime. Attribute is created successfully and also there is no error while reindexing.
Note – I am able to save the attribute value from admin panel.

But while sorting I am getting below error –
No mapping found for [added_on_value.sort_added_on] in order to sort on

Please let me know if anyone has any idea what I am missing. Thanks in advance.