function hideDhtml(mode) {
  
	  var xhr=null;
	  
	  if (window.XMLHttpRequest) { 
	      xhr = new XMLHttpRequest();
	  }
	  else if (window.ActiveXObject) 
	  {
	      xhr = new ActiveXObject("Microsoft.XMLHTTP");
	  }
	  
	  xhr.open("POST", "/ajax.php", true);
	  
	  //on definit l'appel de la fonction au retour serveur
	  xhr.onreadystatechange = function() {
		  if(xhr.readyState == 4 && 200 == xhr.status){
				//alert(xhr.responseText);
				if(xhr.responseText == "ok"){
					document.getElementById("dhtml").style.display="none";
				}
		  }
	  }
	
	  xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	  
	  if (document.getElementById('check').checked || mode == 'force') {
		var data = "hide_dhtml=1";
	  } else {
	  	var data = "hide_dhtml_temp=1";
	  }

	  xhr.send(data);

}