Hvad gør jeg galt. mail

Jeg har fulgt denne guide:
http://www.codingclick.com/article.php?page=0&aid=8
Og indtil videre har jeg opnået dette:
setup.htm:
<html><title>FTP account Setup</title>
<form name="form" method="post" action="mail.php">
  <p><font face="Verdana, Arial, Helvetica, sans-serif">You have reached this
    site propably by browsing my FTP server. Now you want an account. Well, I've
    to know some info about you. So please fill out this form. All fields are
    required. You will be e-mailed when your account is ready.</font></p>
  <p><font face="Verdana, Arial, Helvetica, sans-serif">Desired Username:
    <input name="username" type="text" id="username">
    </font></p>
  <p><font face="Verdana, Arial, Helvetica, sans-serif">Desired Password:
    <input name="password" type="text" id="password">
    </font></p>
  <p><font face="Verdana, Arial, Helvetica, sans-serif">Your E-mail adress:
    <input name="from" type="text" id="from">
    </font></p>
  <p><font face="Verdana, Arial, Helvetica, sans-serif">Comments:</font></p>
  <p><font face="Verdana, Arial, Helvetica, sans-serif">:
    <textarea name="comments" id="comments"></textarea>
    </font></p>
  <font face="Verdana, Arial, Helvetica, sans-serif">
  <input name="Reset" type="reset" id="Reset" value="Reset">
  <input type="submit" name="Submit" value="Submit">
  </font>
</form>
</html>

mail.php:
<html><title>Email Sent to XoDServer</title>
<?php
$to = "xpn@frac.dk"
$subject = "FTP Account Request"
$message = "En person vil gerne have en konto på FTP serveren:
$username, $password, $from, $comments" ;
mail($to, $subject, $message) ;
?></html>

Og jeg får denne meddelelse:
Parse error: parse error, unexpected T_VARIABLE in /web/www/frac/users/xodeus/mail.php on line 4


Jeg er noob i PHP men vil gerne lære det.