Kudos to Wray at WishList Member support for bring this blog entry to my attention.
This is how I implemented it for my WordPress Blog (actually a fully functional Membership Site thanks to the WishList Member plug-in)…
In pluggable.php:
// Set to use PHP's mail()
/*
** Change BHC 2009-06-19: Start
** Windows Server 2003 does not have the Unix SendMail command
*/
//$phpmailer->IsMail();
$phpmailer->IsSMTP();
$phpmailer->SMTPAuth = true; // enable SMTP authentication
$phpmailer->Port = 25; // set the SMTP server port
$phpmailer->Host = 'mail.authsmtp.com'; // SMTP server
$phpmailer->Username = '<smtp username>'; // SMTP server username
$phpmailer->Password = '<smtp password>'; // SMTP server password
$phpmailer->From = '<marketing user>@infoquick.com';
$phpmailer->FromName = '<first name> <last name>';
$phpmailer->Sender = '<support user>@infoquick.com';
$phpmailer->AddReplyTo('<support user>@infoquick.com', '<first name> <last name>');
/*
** Change BHC 2009-06-19: Finish
*/