Please, help me.

I have a perl script. It send e-mail to other people, using sendmail.
How can i get a bounced messages?

May be i must post some special headers or keys?

The part of script:


$from = "from\@host.com";
$to = "to\@host.com";
$subj = "subject";
$letter = "Letter Content";
open MAIL, "|/usr/sbin/sendmail -t";
print MAIL "From: $from\n";
print MAIL "Reply-To: $from\n";
print MAIL "X-Confirm-Reading-To: $from\n";
print MAIL "Disposition-Notification-To: $from\n";
print MAIL "Return-Receipt-To: $from\n";
print MAIL "Return-Path: $from\n";
print MAIL "To: $to\n";

print MAIL "Subject: $subj\n\n";
print MAIL $letter;
close MAIL;