function getParam (name){ 
loc = window.location.toString(); 

var ind=loc.indexOf(name + "="); 
if (ind==-1 || name=="") return null; 
var ind1=loc.indexOf('&',ind); 
if (ind1==-1) ind1=loc.length; 

var valore= unescape(loc.substring(ind+name.length+1,ind1)); 
return valore;
}