Rails - Jul 2006 - help with best practice connection for apache 1.3.x and rails

I''m adding some new content to a legacy system that is using apache
1.3.x, and I was doing some research for the best way to use rails in
this environment.

The system consists of four webservers behind a hardware load-balancer
so I don''t want to/can''t balance on the individual machines. 
I know
some of the methods to setup a new server include apache
2.2/proxy_balancer/mongrel or lighttpd/fcgi, but I can''t do a new
install or upgrade a the current servers because of legacy code.

My research has show that you can use SCGI or mod_fcgi. I was
wondering which of these is currently considered the better method for
stability, performance, etc. Also, is there a better interface that I
could use? (again, without installing a new server).

Thank you.