migration from one server to two

[Roman Kurakin]

Hi,

    I plan to split duties from one server to two. Currently one_server 
is used
among other duties as filtering bridge between Internet and Intranet.

Internet-one_server-Intranet

I wonder, if it is possible to set two servers this way:

Internet-S1-S2-Intraner

and split duties of one using firewall settings, so that they use the 
same IP and
hostname (I want that from both Internet and Intranet they would look 
like one
machine) but for different services. I want to set this just using ipfw. 
I didn't set
such configuration before so I wonder if some one already use such 
configuration
and what problems I could meet while setting this.

rik