#!/usr/bin/php
idn_to_ascii(yhaoo.com) = yhaoo.com<br>
checkdnsrr(idn_to_ascii(yhaoo.com), 'MX') = 1<br>
array(1) {
  [0]=>
  string(0) ""
}
KO<br>

idn_to_ascii(yahoo.com) = yahoo.com<br>
checkdnsrr(idn_to_ascii(yahoo.com), 'MX') = 1<br>
array(3) {
  [0]=>
  string(21) "mta6.am0.yahoodns.net"
  [1]=>
  string(21) "mta7.am0.yahoodns.net"
  [2]=>
  string(21) "mta5.am0.yahoodns.net"
}
OK
idn_to_ascii(dolibarr.fr) = dolibarr.fr<br>
checkdnsrr(idn_to_ascii(dolibarr.fr), 'MX') = <br>