Sort icon(up down arrows) on searchable columns of datatables is not displaying

[IngoPan]

I have a jquery datatable, in which some of the columns are made searchable\[code\]var oTable = $('#genericTable').dataTable( { "bProcessing": true, "sAjaxSource": '<%=jsonPath%>' + key + ".json", "sPaginationType" : "full_numbers", "bJQueryUI" : true, "bRetrieve" : true, "bPaginate" : true, "bSort" : true, "aaSorting" : [[ 2, "desc" ]], "iDisplayLength" : 50, "bAutoWidth" : false, "aoColumns": [ { "sTitle": "Name", sWidth: '200px' }, { "sTitle": "Description", sWidth: '360px' }, { "sTitle": "Date", sWidth: '70px', "sType": 'date-uk' }, { "sTitle": "Action", sWidth: '60px', "bSortable": false } ], }).columnFilter({ sPlaceHolder: "head:after", aoColumns: [ { type: "text" }, { type: "text" }, null, null ] }); } );});\[/code\]The columns which are searchable (textbox displaying in header to search) does not have updown arrow icon right to textbox, while other column header have this sort iconMay i know What can be the solution to display sort icon next to textbox in column header??