Парсер вмида по кошельку

function return_wmid($purse) {
$request="<request><purse>$purse</purse></request>";
$url="https://passport.webmoney.ru/xml/XMLGetWMIDInfo.aspx";
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch, CURLOPT_POST,1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $request);
$result=curl_exec($ch);
$xmlres = simplexml_load_string($result);
$wmid=$xmlres->certinfo->wmids->row[wmid];
return $wmid;
}