This is actually the wrong forum for this -- there is an ORDS forum.
However, I had a similar issue and I got what I needed working by using tuckey's URLREWRITE in tomcat.. I had a requirement where only certain applications could be accessible through one ORDS installation.. and that all pages must be HTTPS.
In your case, it would be that you'd want to filter on f?p=?:101 -- page 101 is normally the default login page for apex apps.. and redirect to the https version of it