thead:after doesn't work

[GoogleCodeExporter]

try to use columFilter with sPlaceHolder: "thead:after"

i use :
jquery 1.8.1
datatables 1.9.3
columnFilter 1.5.0

my table is :

<table align="center" border="1" id="tatable">
                <thead>
                <tr>
                    <th scope="col">Numero de la prise</th>
                    <th scope="col">Description</th>
                    <th scope="col">Piece</th>
                    <th scope="col">Action</th>
                </tr>
                <tr>
                        <th></th>
                        <th></th>
                        <th></th>
                        <th></th>
                    </tr>
                </thead>
                <tfoot>
                    <tr>
                        <th></th>
                        <th></th>
                        <th></th>
                        <th></th>
                    </tr>
                </tfoot>
                <tbody>
// a lot of data
</tbody>
</table>

my jquery code for initialisation is : 

$(document).ready(function(){
    $('#tatable').dataTable({
                "bLengthChange": false,
                "iDisplayLength":50    
    }).columnFilter({
        sPlaceHolder: "thead:after",
        aoColumns :[
            {type: "text"},
            {type: "text"},
            {type: "text"},
            {type: "text"}
        ]
        }
    );
});

and this code display 2 row on header and inputs is on bottom of the table ... 
WHY ??? 

Original issue reported on code.google.com by andrel...@gmail.com on 14 Sep 2012 at 5:59

[GoogleCodeExporter]

I think it's :

 sPlaceHolder: "head:after",

Original comment by cha...@gmail.com on 26 Oct 2012 at 3:48

[GoogleCodeExporter]

It is "head:after", but it does not seem to work with datatables 1.9.4

Original comment by brun...@corollarium.com on 28 Mar 2013 at 8:10