use CGI;
use Lock;
local $main::highlander = Get Lock(
    lock_file => "highlander",
    timeout_limit => 10;
);
unless ($main::highlander) {
    my $host = $ENV{REMOTE_HOST};
    $host = $ENV{REMOTE_ADDR} unless defined $host;
    warn "$0 @ ".(localtime).": highlander abort for $host after 10 seconds\n";
    print CGI::header(-status => 503,
                      -retry_after => 30,
                      -type => 'text/plain'),
                        "Our server is overloaded.  Please try again in a few minutes.\n";
    exit 0;
}
# No further logic required for mod_perl!!!