Not sure if it's "Guaranteed", but there are a couple of other options:

• Mail:Mailer allows you to specify the mail transport.
• MIME::Lite allows you to specify that mail be sent without the use of any external transport, via direct SMTP connection. This module has its own transport, and thus will even work on a barebones Win32 system that lacks sendmail or equivilant.

If sendmail is installed (vs another mailserver), is it in /usr/bin or elsewhere? If the Mail::Sendmail or Mail::Send modules are installed, are they properly configured? What mailserver accepts mail from the webserver running the perl processing the form? Does that mailserver accept mail from user 'nobody' or whatever UID is running the code?

sub vianetsmtp
{
my $from     = $_[0];
my $to        = $_[1];
my $subject     = $_[2];
my $body     = $_[3];

$smtp = Net::SMTP->new    ($maileroutrelay,
            Timeout => $mailerouttimeout,
               Debug   => $maileroutdebug
                  ) or logtofile ($logdir.'/usermailer',"can't create 
+new smtp mail object");
defined ($smtp) or die;
my $domainmessg = $smtp->domain;
my $bannermessg = $smtp->banner;
$smtp->mail($from);
$smtp->to($to);
$smtp->data;
$smtp->datasend("from:$from");
$smtp->datasend("\n");
$smtp->datasend("subject:$subject");
$smtp->datasend("\n");
$smtp->datasend("$body");
$smtp->datasend("\n");
$smtp->quit;
undef $smtp;
logtofile ($logdir.'/usermailer',"usermailer: mail written via net::sm
+tp");
return 1;
}
[download]

/usr/bin/sendmail
/usr/share/man/man8/sendmail.8.gz
/usr/ports/mail/sendmail
[download]

open (MAIL, "|$mailprog -t") or &dienice("Can't access $mailprog!\n");
    print MAIL "To: $FORM{'my_email'}\n";
    print MAIL "Reply-to: $FORM{'email'}\n";
    print MAIL "From: \"$FORM{'fname'} $FORM{'lname'}\" \<$FORM{'email
+'}\>\n";
    print MAIL "Subject: Transaction Notification\n\n";
    print MAIL "$emailbody\n";
    close(MAIL);
[download]