function saveCookie(name,value,days,domain)
{
    var domainStr="";
    if (domain)	domainStr = "; domain="+domain;
    if (days) {
	var d = new Date();
	d.setTime(d.getTime()+(days*24*60*60*1000));
	var ex = "; expires="+d.toGMTString();
    }  else {
	var ex = "";
    }
    document.cookie = name+"="+value+ex+domainStr+"; path=/";
}
function eraseCookie(name){saveCookie(name,"",-1);}
function readCookie(name)
{
  var eq = name + "=";
  var ca = document.cookie.split(';');
  for(var i=0;i<ca.length;i++) {
    var c = ca[i];
    while (c.charAt(0)==' ') c = c.substring(1,c.length);
    if (c.indexOf(eq) == 0) return c.substring(eq.length,c.length);
  }
  return null;
}