I'm not sure I understand the question correctly, so let me rephrase :
- You have an Apache Server running on you local machine
- You normally use a Proxy to connect to the internet
- This proxy has a .pac config file
- You want to access your local Apache Server from the Internet
- I didnt understand what SSH and AjaxTerm do in this picture.
First, this doesnt look like a programming question, so you are probably better asking it on the Apache mailing list. That said, there is probably some misconceptions. The proxy you use to access the internet is what we could call a "forward proxy", it handles the traffic going from a client inside your company to a server outside of your company.
What you need is a "reverse proxy", which handles the traffic from a client outside of your company to a server inside of it. (Note that both functions can be configured on the same proxy - a proxy can be at the same time a reverse proxy and a forward proxy).
The .pac file that you have is a way to configure your browser to go through the proxy to go to the internet. What you need is to configure the proxy to forward traffic to your webserver. This configuration will not be done in your local Apache server, but on the proxy itself. So you'll have to talk with the administrator of this proxy ...