Originally Posted by acid_kewpie
you don't need to add them anywhere. What doesn't thunderbird like about using the mydomain.net name?? If you want to make the server available by other names, that would go on your DNS service, whatever that is.
From what I can see Thunderbird must have something.mydomain.com and the same for eM Client. Gmail is better as whilst it will do the same it lets you edit it on error.
Presume you meed my local DNS but have no idea of implementing it.