Add this to your script to reveal the source of the 500 error fairly reliably. If you still get a 500 error then the script is not executable, the permissions are wrong or the shebang line is wrong.

# ensure all fatals go to browser during debugging and set-up
# comment this BEGIN block out on production code for security
BEGIN {
    $|=1;
    print "Content-type: text/html\n\n";
    use CGI::Carp('fatalsToBrowser');
}
[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print