DT_RowId not displayed in id attribute for each row

I'm using DT v1.9 with server side processing.

It looks like have the correct JSON from the server.

{"sEcho":1,"iTotalRecords":38524,"iTotalDisplayRecords":38524,"aaData":[{"DT_RowId":1,"0":9294,"1":"SMITH, JOHN","2":null,"3":"Aug 11 1982 12:00AM","4":"School XYZ","5":"123 street","6":"Somewhere ","7":"CA","8":"93105","9":"School ABC","10":"Nov 24 1987 12:00AM","11":"Jun 2 1988 12:00AM","12":0}...

However, shouldn't this row have an id of 1 in the html since the DT_RowID is set to 1? Instead it has a row ID of 9294. Any ideas why this is happening?

<tr id="9294" class="odd">

Thanks,
Mike