vroom makes a good point. If you're going to be packaging up your goodies for the less technically inclined, it shouldn't be all that hard to embed a good cron module into your package. The same goes for any module that isn't part of the perl core, but would save you development time and offer a well-tested solution for issues that might otherwise be tricky for you or even risky for users of your package.
Of course, when the CPAN module you embed or adapt into your package undergoes an important fix, you'll need to update your package accordingly. This could also be a very good feature for customers who are not "CPAN-enabled" -- they need only rely on you to make sure that their installation takes care of all that bug-fix/web-security stuff, so long as they just keep up to date on this one complete package that they get from you.