More than one installation on the same machine

Hi, I'm using Postgresql as the database for my
website (which is running Apache and mod_perl), and I
want to upgrade my database from 7.2 to 7.3, but I'd
like to test that everything's working before I make
the switch on my live site. The problem is, it's the
same machine running both my development and live
environments.

I've installed 7.3 in its own directory, using the
default configuration parameters, and I gather from
the 7.3 documentation that I need to start it up on a
different port and provide a different socket to point
DBI::Pg at. (7.2 has port 5432 and a socket in /tmp)
But I couldn't figure out quite how to do it, based
on the documentation. If anyone can provide me with
more detailed instructions (or point me at them if
they're out on the web somewhere), I'd be much
obliged.

Thanks,
Jay

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