APACHE Reverse Proxy

[farnoise]

Hi Everyone,
I started a APACHE reverse proxy server in my network and I'm havbingsome issues with it, Apache is on a Win XP machine and we have couple 2008 Srvr in network with 5 Public IP.

We just installed a App on our IIS 7.5 SRvr and what i'm trying to do is give this app a Virtual name in proxy so peple can use this app from outside of our network using our .CA domain that we have and I pointed to this proxy srvr.

So every time I'm trying to hit this app "Inter.Compnaysite.ca/APP" I can see in the address bar that browser can read the address as it says "/index.php?action=Login&module=Users&login_module=Home&login_action=index" but in the body of the page it says:
"
NOT FOUND
The requested URL /index.php was not found on this server.
"

here is my code to that local srvr

ProxyPass /APP

http://192.168.1.50:896/

ProxyPassReverse /APP

http://192.168.1.50:896/

I should mention that I have a Sync app for iPhone on the same srvr that I can totally use it through proxy but not this one.

And one more PS: I can access this APP internally by just typing

http://192.168.1.50:896/

in the address bar and it'll take me to that URL that I mentioned earlier,

Any hint will be much appreciated.