Multiple routing table clarification

[Angelo Turetta]

I need to run squid, serving different networks with different 
(potentially conflicting) IP address schemes.

I read the original implementation notes for setfib/multiple routing 
tables: 
http://perforce.freebsd.org/fileViewer.cgi?FSPC=//depot/user/julian/routing/plan.txt

and I would like to ask for some clarifications:

- is it possible for a single process to listen for TCP connections 
using  more than one socket, each with its own 'fib'?

- if I use ipfw rules to tag incoming traffic, can I force the fib on a 
incoming TCP connection to be different from the fib of the 
process/socket listening for that connection?

Thanks for any help (oh, BTW, if somewhere more detailed howto/doc about 
this feature can be found, please forward any pointers)

Angelo.