Multiple Jigsaw instances

Hi
I would like to run multiple instances of Jigsaw on one machine. Jigsaw
is configured to run as a proxy.
The reason is that I would like to utilize both processors in a dual CPU
maching running Linux 2.2.x. I can't do that with one instance of Jigsaw
since I use (and should use due to different circumstances) a runtime
that uses a many-to-one threading model.
Therefore Jigsaw consists of one process only, which of course only can
utilize one CPU at a time.

What are the implications of running (for example) two instances of
Jigsaw?
I was thinking that maybe I could just use different (http and admin)
server tcp ports and different "-root" directories.
If this is a possible way to do it, then how can I change the admin
server port so that the instances doesn't conflict? (I cannot find a
command-line argument for it)

Best regards
Niklas Wiberg