I want to setup control on mails to a groups.
Say i want to allow only a group of member to send mails to a particular group.
I will create a group firstname.lastname@example.org and add every account in example.com
I want only email@example.com and IT@example.com group members to be allowed to send mail to firstname.lastname@example.org
Rest all others i want to deny.
Please provide me solution to accomplish this.