grid sort column date(d/m/y) does not work

hello, I need help I’m using the grid control I need to implement sorting of data for colonna.il problem arises with the use of date d / m / y sorting is done only for the day and not for d / m / y
You can see the problem going on cof.unict.it/CofCv

choose:
law faculty =
law degree = (lt 085) students: 53
click on search

the code I used is as follows:

mygrid = dhxtabbar.cells(“a1”).attachGrid();
mygrid.setImagePath(patdhtmlxGrid);
mygrid.loadXML(patxmlgrid,function(){
mygrid.setSizes();
setGrigliaphp(responseText,mygrid);
dhxtabbar.setTabActive(“a1”);
});

mygrid.setInitWidths("100,250,80,*");
mygrid.setColAlign("center,center,left,right");	
    mygrid.setColTypes("ro,ed,ro,ed");
    
mygrid.setColSorting("int,str,dhxCalendar,str,date,str");
   // mygrid.setColSorting("int,str,date_custom,na,str");
   // mygrid.setCustomSorting(date_custom, 2);
   // mygrid.setDateFormat("%d/%m/%Y");
   mygrid.init();
mygrid.setSkin("dhx_skyblue");

function setGrigliaphp(responseText,mygrid){

var tail = responseText.split("tail");
var res = responseText.split("|");
var maxele= res.length;

mygrid.clearAll();

for(var i=0; i< maxele; i++){

    campi = res[i].split("*cld*");     
   mygrid.addRow(i,[campi[6],campi[1],campi[2],campi[3],campi[4],campi[5]]);
}

}

You should define date format in grid using setDateFormat() method
docs.dhtmlx.com/doku.php?id=dhtm … dateformat