comment out the original pun_mail and use this one to try to send it again. sounds like an email address is being truncated.
function pun_mail($to, $subject, $message, $from = '')
{
global $pun_config, $lang_common;
// Default sender/return address
if (!$from)
$from = '"'.str_replace('"', '', $pun_config['o_board_title'].' '.$lang_common['Mailer']).'" <'.$pun_config['o_webmaster_email'].'>';
// Do a little spring cleaning
$to = trim(preg_replace('#[\n\r]+#s', '', $to));
$subject = trim(preg_replace('#[\n\r]+#s', '', $subject));
$from = trim(preg_replace('#[\n\r:]+#s', '', $from));
$headers = 'From: '.$from."\r\n".'Date: '.date('r')."\r\n".'MIME-Version: 1.0'."\r\n".'Content-transfer-encoding: 8bit'."\r\n".'Content-type: text/plain; charset='.$lang_common['lang_encoding']."\r\n".'X-Mailer: PunBB Mailer';
// Make sure all linebreaks are CRLF in message
$message = str_replace("\n", "\r\n", pun_linebreaks($message));
if ($pun_config['o_smtp_host'] != '') {
echo "<p>smtp_mail sending to: $to</p>";
smtp_mail($to, $subject, $message, $headers);
} else
{
// Change the linebreaks used in the headers according to OS
if (strtoupper(substr(PHP_OS, 0, 3)) == 'MAC')
$headers = str_replace("\r\n", "\r", $headers);
else if (strtoupper(substr(PHP_OS, 0, 3)) != 'WIN')
$headers = str_replace("\r\n", "\n", $headers);
echo "<p>php_mail sending to: $to</p>";
mail($to, $subject, $message, $headers);
}
}
you should see some debug info, and it will print out the email addresses as they are sent. if they show up truncated, then its getting messed up along the way.
once you get it figured out, you'll want to remove this function & use the old one.