First things first: What I am trying to do is create a very simple postfix filter. it'll examine each message and upon finding a word, it will replace that word with another word, and inject the modified email back into the postfix queue. Here's what I have done so far: 
#!/usr/bin/perl

use Mail::Internet;
$msg = Mail::Internet->new([ <> ]);

$to = $msg->get('To');

#$content = join( '',@{$msg->body} );

@content = @{$msg->body};

print "To: " . $to;

foreach $line (@content) {
        @words = split(/ /, $line);
        foreach $word (@words) {
                if ($word =~ /blah/) {
                        $word = "something";
                }
                print "$word ";
        }
}

[download]
So, upon finding "blah" it will replace it with "something". here's a test email that I fed into it: 
From root@val.vmsinfo.com  Fri Dec 14 14:54:57 2007
Return-Path: <root@val.vmsinfo.com>
X-Original-To: vxp
Delivered-To: vxp@val.vmsinfo.com
Received: by val.vmsinfo.com (Postfix, from userid 0)
        id 86A085FD705; Fri, 14 Dec 2007 14:54:57 -0500 (EST)
To: vxp@val.vmsinfo.com
Subject: hi
Message-Id: <20071214195457.86A085FD705@val.vmsinfo.com>
Date: Fri, 14 Dec 2007 14:54:57 -0500 (EST)
From: root@val.vmsinfo.com (root)
Status: O
X-Status: 
X-Keywords:                  
X-UID: 7

hi Val blah some more blah
..

[download]
and here's the resulting output: 
[vxp@val ~]$ ./mail.pl test.txt
To: vxp@val.vmsinfo.com
hi Val something some more something ..
 [vxp@val ~]$

[download]
Now, as you see, the "\n" before the second line was lost in the output: the ".." is now on the first line.. Any suggestions ? :)

In reply to A regex question by vxp

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