Yes, this task is very difficult to do right without a module, and I won't explain it here, as explaining it means reformulating the mbox manpage (found here for example) and Mail::Box handles it very nicely. I have only used Mail::Box after version 2, but I guess that the basic methods haven't changed that much since :

#!/usr/bin/perl -w

# Some vestige of local delivery
# For another method, have a look at Mail::LocalDelivery

use strict;
use Mail::Box;
use Mail::Box::Manager;
use Mail::Message;
use Mail::Message::Construct;

use vars qw($localmailbase $foldername);
use vars qw($mgr $folder);

$host = 'hera.informatik.uni-frankfurt.de';
$localmailbase = "/home/corion/mail/";
$foldername = "informatik";

$mgr = Mail::Box::Manager->new(folderdir => $localmailbase,
                               default_folder_type => 'mbox',
                               );
$folder = $mgr->open( folder => $foldername, access => 'rw', create =>
+ 1 );
die "Couldn't open mailfolder '$foldername' : $!\n" unless $folder;

print "Using folder ",$folder->name,"\n";
my %messageIDs;
%messageIDs = map { $_->get("Message-ID"), $_ } ($folder->messages);

my $msg;
foreach $msg ($folder->messages) {
  print "*** The content of this message is :\n";
  print $msg->body;
}

$mgr->close($folder);
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I don't have access to any older Mail::Box documentation at the moment, but each message should have the body method, which returns the body of the message as a string.

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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