I'm an experienced perl programmer, and am having difficulty

Hello, lyman and welcome to the Monastery. As an experienced Perl programmer you will be well aware that the best thing to do when asking for help with a specific problem such as this is to provide an SSCCE. That will ensure that the answers provided will address the specific problem rather than any vague description such as "It needs an XS.pm".

If you can provide that then I am sure you will receive a wise and relevant response in short order.