Ok.. update .. This is much better now, fixed some stupidity with mimetypes, this is actually important so the client will know what to do with the data.

i installed File::MMagic on the server and here's the code to my downloader.. i high-lighted what applies here.

#!/usr/bin/perl -T
=pod

    DOWNLOAD A FILE
    does not need to be sent form data, it makes a temp download link 
+from the last selected file

=cut    

use strict;
use lib 'xxxxxxxxxxxx';
use DMS; 
use DMS::Admin;
use DMS::Database;
use DMS::Shared;
use Hstat;
use File::MMagic;



#first test and sanitize all tainted data
my %FD=DMS::tainted_data; #will poop out on its own if bad

my $db=DMS::Database::dbstart;

#/////////    THIS IS THE DOG ////////////////////////////////////////
+/////
my %SV = DMS::Database::SV('u,m',\$db,\%FD);
#then get all form data that may exist


if ($SV{usertype} eq 'u'){

    #make sure they have rights over file id
    my $c=$db->prepare(qq|select users_id from files_users where users
+_id="$SV{users_id}" and inode="$SV{file_selected}"|);
    $c->execute;
    unless($c->rows){
        #user has no rights to file.
        $c->finish;    
        $db->disconnect;
        print "Location: $WWW?you.do.not.have.rights.to.that.file.u\n\
+n";
        exit;
    }
    $c->finish;
} elsif ($SV{usertype} eq 'm'){
    
    #find parentmost's inode
    unless ( find_parentmost($SV{file_selected},\$db) eq $SV{project_s
+elected} ){
        $db->disconnect;
        print "Location: $WWW?you.have.no.rights.to.that.file.m.$SV{pr
+oject_selected}.$SV{users_id}\n\n";
        exit;
    }
    #$q->finish;
    

} # else.. they are admin or superadmin.

$db->disconnect;

#

#stream
my $filename = $SV{file_selected_path};$filename=~s/^.+\///;


# $DOC/$SV{file_selected_path} is something like /my/file/on/server/he
+re.pdf
my $FILE;
if (!open($FILE, '<',"$DOC/$SV{file_selected_path}")) {

   print "Content-type: text/html\n\n
    Sorry $DOC/$SV{file_selected_path}";    
    exit;
}


#ok we are all go.

#find out mime type!!!
my $mm= new File::MMagic; #use internal magic file
my $res = $mm->checktype_filename("$DOC/$SV{file_selected_path}");

print(qq|Content-Disposition: attachment; filename="$filename"\nConten
+t-Type: $res\n\n|);

binmode(STDOUT);
binmode($FILE);
$/ = \1024; # Read in blocks of 1024 bytes;
print while <$FILE>;
exit;
#

sub find_parentmost {
    my ($inode,$db)=@_;
    #my $parent=1;
    my $q=$$db->prepare(qq{SELECT link FROM files WHERE inode=?});
    
    my $parentmost;
    
    while ($inode){
        $q->execute($inode);    
        $parentmost=$inode;
        ($inode) = ($q->fetchrow);
    }    
    $q->finish;
    return $parentmost;    
}
[download]

Edit: g0n - replaced pre with code tags