If the ftp account is on the same host and account as the web server, why not just write the string to a file? CGI.pm makes that really easy with its save method. This does that,

use CGI;
my $q = CGI->new;
open my $fh, '>>', '/path/to/requests.log' or die $!;
$q->save($fh);
close $fh or die $!;
[download]

I'll leave printing the html responses to the remote client as an exercise ;-)

You can exhibit the output of perldoc perllocal to see which modules are installed by standard EU::MM methods.