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At one of my installation, the user demand that this particular distribution list eg. all@domain.com which lists all users in that domain, can only be sent to by only one or some authorized users eg. admin@domain.com.
Right now, the all@domain.com is being abused by users and need some action to be taken.
This is not so useful when you have many distribution lists and only their members can send emails to them. Because you would have to crate as many restrictions as lists you might want to have.
Bugzilla
Wiki
Source
Restrict distribution list access 
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