Can't be done Batch.
In name-based virtual hosting, also called shared IP hosting, the virtual hosts serve multiple hostnames on a single machine with a single IP address.
When a web browser requests a resource from a web server using HTTP/1.1 it includes the requested hostname as part of the request. The server uses this information to determine which web site to show the user.
If you had the full server path to the forum index page like http://78.129.192/thetownend/htdocs/forum/index.php then that would probably work.