Adding sub-rows dHtmlx but no show

Question

i'm newbie for using dhtmlx, i tried to create table with sub-rows but i got nothing. this is my table using dhtmlx:

and this is my current code:

mygrid3 = new dhtmlXGridObject('gridbox3'); 
mygrid3.setImagePath("{baseurl}/includes/javascripts2/dhtmlx/dhtmlxGrid/imgs/");
mygrid3.setSkin("dhx_skyblue"); 
mygrid3.enableCollSpan(true);
mygrid3.enableDistributedParsing(true,1,0.1);   
mygrid3.enableAlterCss("even_row","odd_row");

mygrid3.setHeader("{header1}");
mygrid3.attachHeader("{header2}");
mygrid3.attachHeader("{header3}");

mygrid3.setInitWidths("{cellwidth}")
mygrid3.setColAlign("{cellalign}")

mygrid3.init();

$j(document).ready(function(){

        $j.blockUI(
            { message: $j('#domMessage') }
        );
    mygrid3.loadXML("{xmlsource3}",calculateFooterValues3); 

});

i have adding setColType() but it not works. any ideas??