In your Makefile.PL:
use inc::Module::Install; ... requires_list; ...
From the command line:
> perl Makefile.PL > make requires-list
This module adds a target to your Makefile for listing the modules required.
The report is broken into sections: Required, Recommended, Build Requires, and Author Requires.
For each module listed, the report prints 3 versions: the version you are requesting, your installed version and the CPAN version.