I had the idea of implementing a workflow module for e-mail communications, something like this:
User role 1 can write e-mails (as nodes or custom entities) User role 2 can review and approve e-mails User role 3 can press send
I would then like the website to catch replies and enter them into the database with reference to the user entities that touched the e-mail entity, so that the workflow can also be applied to replies. The part that I'm not sure I can do here, is doing advanced e-mail processing based on which users touched the e-mail.
Are there any modules that can handle encoding these entity references into the reply-to or message of the e-mail so that the Drupal site can process the replies dynamically?