This is an original and free add-on product for cPanel/WHM. The product provides you with an interface to the cPanel user accounts email configuration without having to login to their accounts. It is domain based rather than account based and allows you to do all the following from within WHM:
The latest version of cmm can be downloaded here: cmm.tgz
Please visit our ConfigServer Scripts Forum
This application is released under our script license. It is released free of charge, with no warranty to its suitability. There is no support provided with this application except through our online help forums.
If you don't feel confident doing any of this yourself, or if you get into a horrible mess, we do have cPanel Server Services that include the installation and configuration of this application.