Sort breaking on first column after delayed ajax load

avi.diadeis

I'm using datatables with ajax and delayed loading after the initial load (only) my second column wont sort right
clicking on the column head posts a draw to the server however the sort dir is missing and never comes back

see from firebug
draw
11
length
10
order[0][column]
1

my column then switches to the unsorted icon look and will not sort
initial sort is column 1 desc

sorting by any other column first "fixes" it and then i can sort on second column normally

$('table').dataTable({
            "scrollCollapse": true,
            "oLanguage": {
                "sSearch": "Search all columns:",
                "sInfoFiltered": ""
            },
            "lengthMenu": [[10, 25, 50, 100, 250, 500, -1], [10, 25, 50, 100, 250, 500, "All"]],
            "autoWidth": true,
            "pagingType": "full_numbers",
            "paging": true,
            "processing": true,
            "serverSide": true,
            "ajax": {
                "url": "/DataTable/draw/",
                "data": function ( d ) {
                        d.Model = custDataModel;
                },
                "type":"POST"
            },
            "order": ["1","desc"],
            "columns": [
                {
                'data':'order_id',
                'name':'order_id',
                'mRender':drawCheckBoxDetail,
                'className':'DTactionButton',
                'orderable':false,
                'sWidth':'35px'
                },
{
                'data':'order_num',
                'name':'order_num'
                },
{