Any other suggestions?

#!/usr/bin/perl -w

use strict;
use warnings;
use POSIX;
use CGI qw/:standard/;
require SDBM_File;

my %sig;
my $sigsave = "sig.dbm";
my %emails;
my $list      = "list.dbm";
my $adminmail = "admin\@test.com";
my $sendmail  = "/usr/lib/sendmail";
my $signature;

tie %emails, 'SDBM_File', $list, O_CREAT | O_RDWR, 0644;
if ( !tied %emails ) {
    print "database unsuccessful $!.\n";
}

tie %sig, 'SDBM_File', $sigsave, O_CREAT | O_RDWR, 0644;
if ( !tied %sig ) {
    print "database unsuccessful $!.\n";
}

print header, start_html('Email Management');

print "DB contents: $sig{$signature}\n";

print start_form(), table(
    Tr(
        td("Subject: "),
        td(
            textfield(
                -name => 'subject',
                -size => 40
            )
        )
    ),
    Tr(
        td("Message: "),
        td(
            textarea(
                -name    => 'message',
                -columns => 40,
                -rows    => 5
            )
        )
    ),
    Tr(
        td("Signature: "),
        td(
            textarea(
                -name    => 'signature',
                -default => $sig{$signature},
                -columns => 40,
                -rows    => 5
            )
        )
    ),
    Tr(
        td(
            checkbox_group(
                -name    => 'todo',
                -values  => [ 'use', 'save' ],
                -rows    => 2,
                -columns => 2
            ),

        ),
        td(submit)
    ),
  ),
  end_form(), hr();

# rid ourselves from those nasty params
my $message   = param('message');
my $subject   = param('subject');
$signature = param('signature');
my $todo      = param('todo');

if ( param() ) {
    if ( $message && $subject eq "" ) {
        print "Your subject or email content was missing.\n";
    }
    else {
        foreach my $key ( keys %emails ) {
            print "Things we have: $key <br>\n";
        }
        print "<br>\n";

        while ( my ( $key, $value ) = each(%emails) ) {

            # Email Subs, special commands
            $message =~ s/\[name\]/$value/;    #[name] = user name

            open( MAIL, "| $sendmail -t" );
            print MAIL "To: $key\n";
            print MAIL "From: $adminmail\n";
            print MAIL "Subject: $subject\n\n";
            print MAIL "$message\n";
            if ( $todo eq "use" && $signature ne "" ) {
                print MAIL "$signature\n";
            }
            print MAIL ".\n";
            close(MAIL);

            print "Email was sent to: $key !<br>";
        }
    }
    if ( $todo eq "save" ) {
        print "<br>";
        print "Saving to database<br>\n";
        $sig{$signature} = $signature;
        print "\$sig{\$signature}: $sig{$signature}";
    }

}
untie %emails;
untie %sig;
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