function zlist_encode(param)
{
    var ret= '';

    for (var i=0; i < param.length; i+=2) {
	if (ret.length)
	    ret += '&';
	ret += encodeURIComponent(param[i]) +'='+ encodeURIComponent(param[i+1])
    }

    return ret;
}

function zlist_fetch(func, param)
{
  var request = false;
  var formdata = null;

  if (window.XMLHttpRequest)
    request = new XMLHttpRequest();
  else if (window.ActiveXObject)
    request = new ActiveXObject('Microsoft.XMLHTTP');

  if (!request)
    return false;

  request.open ('POST', zlist_urlbase + 'ajax.php', false);

  formdata = 'function='+ encodeURIComponent(func);

  if (param)
      formdata += '&' + zlist_encode(param);

  request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

  request.send(formdata);

  return eval(request.responseText);
}

function zlist_valid_email(email)
{
    return zlist_fetch('check_email', ['email', email]);
}

function zlist_valid_url(url)
{
    return zlist_fetch('check_url', ['url', url]);
}