In which case, and if you want to bounce the mail straight to someone else, then why not have perl open a conention and have a conversation with the smtp server.

mailbody should contain the data, recieved headers and all.

use Net::SMTP; 
# Yes, this is cribbed straight from node 'How 
# do I send e-mail from my Perl Program?'

# You need to fill in the variables.
# Read the perldoc for more info on using SMTP.

my $smtp = Net::SMTP->new("$mailserver") or die $!;
$smtp->mail( $forward_from );
$smtp->to( $forward_to );
$smtp->data();
$smtp->datasend($mailbody);
$smtp->dataend();
$smtp->quit();
[download]

Where $mailbody should contain the original header (starting with Received:) and body of the email, seperated by an extra /n.

References: Answer: How do I send e-mail from my Perl Program? by Adam