Work notes and comments are not getting updated on an extended incident table

Hi All,

I have extended the incident table and created a new table. The problem is when I post a work note or a comment, it does not get updated in the activity stream under the notes tab. I have selected all - in the Activity Filter yet I don't see the work notes and comments there even after I save the incident.

For an OOB incident table work notes get appeared as soon as I hit the POST button. 

I have read a couple of documents related to this and the solution to this was to activate auditing for the newly created table by navigating to Definition/ Dictionary and find the Table Name/ Type = Collection field and activate Audit. But for some reason the newly extended table name is not available in System Definition/ Dictionary. (Maybe because it is an extended table, I do not know !)

Expecting help on this. Thanks.