MRTG server routing issue?

Hello, I am new to Linux and MRTG, please forgive my ignorance. I have a Linux server setup running FC4 with MRTG running. The server has two physical NICs. The MRTG program is working. The issue is that I am unable to access my internal IPs through the web Interface from an outside IP. I have eth0 as my external IP and eth1 as my internal.
Any and all help will be greatly appreciated!

you need to configure the Linux as a router, you need to add in static routes, telling the box to forward on the routes to the next interface.

look up "using linux as a router"

its not an MRTG issue