Nevermind.  Figured it out.
    $self->header_props(-status => '404 Object Not Found');
Thomas Rowe wrote:
> I'm using cgiapp under CGI::Application::Server at the moment.  I 
> cannot figure out from the documentation how I'm supposed to set the 
> HTTP response code from a run-mode.  I want to send 404 given certain 
> parameters.
>