PHPMailer wont send to email with Hyphen IE-#blah-blah.com - php

Question

I have a simple contact form that uses PHPMailer to send it's information to the admin. Everything works fine when the results are sent to an e-mail with out a hypen such as blah#blah.com. As soon as I change the address to an e-mail with a hypen like blah#blah-blah.com, I get this error.
"Could not instantiate mail function. Mailer Error: Could not instantiate mail function."
Is this a bug with PHPMailer?
Here's my code
<?php
require_once('class.phpmailer.php');
$question_for = $_POST['question_for'];
$name = $_POST['name'];
$phone = $_POST['phone'];
$email = $_POST['email'];
$company = $_POST['company'];
$comment = $_POST['comment'];
$mail = new PHPMailer(); // defaults to using php "mail()"
$body = eregi_replace("[\]",'',$body);
$mail->AddReplyTo("donotreply#blah-blah.com","DoNotReply");
$mail->SetFrom('donotreply#blah-blah.com', 'DoNotReply');
switch ($question_for) {
case "Sales":
$address = "Sales#blah-blah.com";
$mail->AddAddress($address, "Blah");
$mail->Subject = "Message from Sales";
break;
case "Service":
$address = "service#blah-blah.com";
$mail->AddAddress($address, "Blah");
$mail->Subject = "Message from Service";
break;
case "Career":
$address = "career#blah-blah.com";
$mail->AddAddress($address, "Blah");
$mail->Subject = "Message from Career";
break;
}
$mail->AltBody = "To view the message, please use an HTML compatible email viewer!"; // optional, comment out and test
$mail->MsgHTML("
Question For:".$question_for."<br />
Name:".$name."<br />
Phone:".$phone."<br />
Email:".$email."<br />
Company:".$company."<br />
Comment:".$comment."<br />");
if(!$mail->Send()) {
echo "Mailer Error: " . $mail->ErrorInfo;
} else {
header('Location: http://blah.com/contact/?sent');
}
?>
Checking even more, I see that this works
<?php
mail("test#blah.com", "Test Email", "Testing"); ?>
but this does not
<?php
mail("test#blah-blah.com", "Test Email", "Testing"); ?>