I was having issues some time ago with a sort of portal system called EzPortal on a test board. (I set up a domain specifically for me to test stuff. I need to ensure that everthing will have the exact same conditions.)
The education is as follows:
I need to load portal.php instead of index.php
I have both an index.php and a portal.php
The URL is simply the domain name.
The server is an Apache Server, hosted by netfirms.
I could not use a DirectoryIndex directive. (mod_dir) it is not allowed by my web host.
I know that index.php is the first to load, and as far as I know there is no other way of change the indexing priority.
If I used the REWRITE ENGINE (mod_rewrite) than I would load the portal.php as a replacement of the index.php, and my forum index will not display.
I set up forwarding pages for all index type pages, and came to the conclusion that index.php had absolute priority over all others.
My Solution:
I created a directory within my domain for my forum. example: opendevsource.net/forum/
I setup a mod_rewrite to send opendevsource.net/index.php to opendevsource.net/forum/portal.php
***I'm done now***
If this is hard to understand, let me know so I may clarify the post. My thought process tends to be very difficult to follow. I used to dream in basic, you know.