Отправка почты с вложением из PHP

<?
function XMail( $from, $to, $subj, $text, $filename)
{
$f         = fopen($filename,"rb");
$un        = strtoupper(uniqid(time()));
$head      = "From: $from\n";
$head     .= "To: $to\n";
$head     .= "Subject: $subj\n";
$head     .= "X-Mailer: PHPMail Tool\n";
$head     .= "Reply-To: $from\n";
$head     .= "Mime-Version: 1.0\n";
$head     .= "Content-Type:multipart/mixed;";
$head     .= "boundary=\"----------".$un."\"\n\n";

$zag       = "------------".$un."\nContent-Type:text/html;\n";
$zag      .= "Content-Transfer-Encoding: 8bit\n\n$text\n\n";
$zag      .= "------------".$un."\n";
$zag      .= "Content-Type: application/octet-stream;";
$zag      .= "name=\"".basename($filename)."\"\n";
$zag      .= "Content-Transfer-Encoding:base64\n";
$zag      .= "Content-Disposition:attachment;";
$zag      .= "filename=\"".basename($filename)."\"\n\n";
$zag      .= chunk_split(base64_encode(fread($f,filesize($filename))))."\n";

if (!@mail("$to", "$subj", $zag, $head))
 return 0;
else
 return 1; 
?>