apache/twiki config

[Danny]

I'm trying to install twiki 4.2 on my CentOS 5.1/Apache 2.2 server, by
following the documentation here:
http://twiki.org/cgi-bin/view/TWiki/TWikiInstallationGuide#Basic_Installation

And I'm stuck at running the configure.pl. Browsing to http://<my
server URL>/twiki/bin/configure gives a 403 error. At first I thought
it was a file permission issue, but even setting everything on /twiki
to 777, I still get a 403.

The apache logs show:

client denied by server configuration: /var/www/twiki/bin/configure

So I think it's an apache configuration problem. I'm really a linux/
apache novice. Any body have a clue? Thanks.