This module provides an interface through which users can subscribe to mailing lists run by procmail/smartlist
My shared hosting provider did not permit the use of mailman, but offers the widly used mailing list system smartlist which runs on top of procmail.
It is by far not as user friendly as mailman, but if you do not have the option, then you have to work with what you have, right?
If you are in the same situation, and do not know if your provider offers smartlist or not, then here is a hint. If you created a email list (e.g. examplelist@domain.com) in your providers web panel, and you have to append "-request" to the name (examplelist-request@domain.com) to trigger an action like subscribing/unsubscribing, then you almost certainly work with smartlist.
I used the mailman_manager codebase as a starting point and modified it to work with smartlist. Smartlist_manager works independent from mailman_manager but I suggest to use only one or the other, but not both modules at the same time.
The administer page allows administrators to add or delete lists and program appropriate request addresses to which commands are sent by Drupal via email.