Hide domain name

Hello everyone, I wanted to ask advice on the best way to solve this problem. Our group has absorbed a new company (XXX) and all of mail services are ported on our server(Lotus Domino version 8.0.1). After entering the new domain in our Global Domain as alias and created users, I got little pleasant news that our domain name must not appear on any of the mail sent from new company XXX. This for me is a serious problem because all internal mail, report as sender name the canonical format (CN/OU/O) and if a user forward it to an external contact unfortunately could embarrass the company. I could tell users to delete this data, but the human error is always possible, I would try instead a system to hide these info when using the function Forward or any other function.The only thing that I thought for now is to modify the template of the DB users of the new company so that when they send email all these info are cleared but I don’t know if it is the best solution

Subject: not an easy task

most e-mails will have replies and such where canonical names will appear in e-mail history threads in the body field. It would be a daunting task to remove this as well as the fact that it will compromise the integrity of the e-mail since you’d have to modify it.