How to grant "superuser" permissions


I was wondering if there was a way to grant access to certain users so that they may “manage” other users, particularly in order to:
1- change voicemail password
2- listen to their voicemails online
and other such actions through the online interface

So basically a very limited administrator so that, for example, a manager/technician could manage their employee’s voicemail system without having complete system administration rights over other configurations like trunks, etc.

Thanks for your help!

You mean like the administrators module?