Den kryptere ikke pass

Hey dér.. Jeg er ved at lave et admin system, men der er en fejl..

Når den sætter ind i mysql så kryptere den ikke pass.. Pass cellen bliver bare tom.. Hvorfor det??
Script:

<? include("header.php"); ?>
<table cellpadding="0" cellspacing="0" id="insidetable">
<tr>
      <td id="insidetd" valign="top">
<?PHP
if($sub){
mysql_query("INSERT admin (user,pass,rang) VALUES ('$_POST[user]','$pass','$_POST[rang]')");

print "<script language=\"javascript\">location.replace('admin.php');</script>";

$pass = md5($notpass);

} else {
?>
<form action="admin.php" method="POST">
<table>
<tr>

<td width="40">User:</td> <td><input id="formfield" type="text" name="user" value=""></td>
</tr>
<tr>
<td width="40">Pass:</td> <td><input id="formfield" type="text" name="notpass" value=""></td>
</tr>
<tr>
<td width="40">Rang:</td> <td><input id="formfield" type="text" name="rang" value=""></td>
</tr>


<td width="40"></td> <td><input id="submit" type="submit" name="sub" value="add"> </td>
</tr>
</table>
</form>
<?PHP
}
?>








</td>
<td id="insidetd2" valign="top">
<? include("plugins/indexplug.php"); ?>



</td>
</tr>
</table>



<? include("footer.php"); ?>