Reverse proxy - need returned urls to prefix with directory name

I am running a Domino 8.0.2 server on a Solaris 10 server. I am using a proxy server to authenticate a user and I am trying to get the following outcome and when accessing the server.

ServerA: Proxy Server

ServerB: Domino Server

Entering the following URL https://ServerA.website.com/testA/somedir/homepage.nsf

This resolves to ServerB/homepage.nsf

This works ok for accessing a database however any link or graphic does not resolve because it is displaying the following:

https://ServerA.website.com/homepage.nsf/newform?OpenForm

And this fails.

Is there a way to have the returning pages appear as without having to create the directory structure? Redirection rule or substitution rule? Some other proxy settings?

https://ServerA.website.com/testA/somedir/homepage.nsf/newform?OpenForm

Thank you in advance for your help.