function getComune(){  

        try
        { 

    	  var url = "/system/modules/it.italcogimreti/elements/app_impianti/impianti.jsp";
	  var xmlhttp = FactoryXMLHttpRequest();
          var combo = document.getElementById("comune");
          var comune = combo.options[combo.selectedIndex].value;
       
         
           //NON METTIAMO APPOSTO NIENTE
           if(xmlhttp)
           {
            	       	            	     	        	
                   //alert(_comune);
                   xmlhttp.open("POST", url);
                   
                   xmlhttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded');

                   xmlhttp.onreadystatechange = function()
                   {
                        if (xmlhttp.readyState == 4 && xmlhttp.status == 200)
                        {                                                
		                         document.getElementById('comuni').innerHTML = xmlhttp.responseText;
                        }
                   }

                   xmlhttp.send("comune="+comune);         
        } 
       
      }catch(E){alert(E);}

   }