I think that it really depends on what you're doing. If you're releasing the modules to CPAN then no. (I think its obvious that you aren't). So I would think the question would be: Are any of the modules useful on their own?
For example I've been working on an e-commerce system, I have a module for the shopping cart, a module for displaying items, a module for searching the items. None of the modules would be particularly useful on their own so they have some degree of interconnectedness.
You could clean up your scenerio by using OO programming. Make Module 'A' a subclass of 'B','C', and 'D'. That way when you create a new 'A' object, all the functions from all the modules will be availiable to it. Then you don't need to worry about exporting either and module A becomes the key to make the other modules work.