There's a lot of things happening in this area, and if you want to look into doing AI work in Perl I'd advocate you start by checking out:

AI modules on CPAN

perl-ai mailing list

extensive perl AI work on sourceforge

Good luck and have fun -- I've played with the area in the past, and alice in particular can be very fun to work with. One of the advantages of Perl AI work over some others is that a lot of it is quite modular -- something missing from many other parts of AI work.