You don't need to install the module; you can just use it locally (assuming of course that you are allowed to do so on your machine).

I had never used Mail::Sendmail, but I looked at the source on CPAN, and there's nothing prohibiting you from using it in a local directory.

Just for fun, I took a copy of it, renamed it as Postal\Dispatch.pm, (modifying the package name within the file to Postal::Dispatch too, of course), and ran the following program:

#!/usr/bin/perl -w
#
#  Test of local copy of Mail::Sendmail (renamed as Postal::Dispatch
#  to be sure it works on its own :-)).
#

use strict;
use warnings;

use Postal::Dispatch;

my %mail = (
    To      => 'liverpole@myISP.net',
    From    => 'liverpole@golux.com',
    Message => 'Hello to myself from Postal::Dispatch',
);

sendmail(%mail) or die $Postal::Dispatch::error;

print "OK. Log says:\n", $Postal::Dispatch::log;
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And sure enough, I got the mail it sent to my ISP!

The only other change I had to make was to the %mailcfg hash in the Mail::Sendmail module:

    'smtp'    => [ qw( localhost ) ]
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which I had to change, of course, to:

    'smtp'    => [ qw( mail.myISP.net ) ]
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