I'm going to defend sundial's point just a little bit here. Given that the shortest path to keeping this code working is to install CGI.pm manually, there's no urgent reason to migrate to a PSGI system.

Also I think you're overstating the value of strict in this case; it's easy to write a simple and correct and strict-safe CGI program that causes inadvertent scope problems with a persistent execution harness like mod_perl. (Plack less so.)