Certainly it's possible for me to use packages that don't come with the system. It's just difficult. This isn't just a home computer, it's part of a production network at a financial company. I first have to test the package on a spare system. Then I have to get approval from my boss. Then I have to schedule the install for off hours and perform it.

Basically unless a CPAN module provides clearly necessary functionality, I'm going to try to avoid installing it. Thus while the UUID approach is interesting, I don't see enough in it to justify the work of getting that CPAN module installed, as opposed to trying other alternatives. For example, calculating md5 sums on the messages is much easier because that module comes with the Fedora perl installation.