how to setup dkim

[zeus]

Hi,
first of all I'm sorry if I'm boring you with this issue. I would like to setup DKIM for every domain on my server (centos 5.9 64bit, Exim 4.80.1, DA 1.43.0).
I googled for it and I'm confused about results.
What is the right tutorial to follow?
http://www.directadmin.com/features.php?id=1189
http://mikepultz.com/2010/02/using-dkim-in-exim/
Have I to create one openssl for every single domain ?
I didn't try anything because I prefer to ask before to edit something into a on-production server.
Thank you for your support and regards

 

[SeLLeRoNe]

http://www.directadmin.com/features.php?id=1189

This is the one to follow.

Regards

 

[zeus]

Mille grazie Andrea.
Everything seems to be fine, thanks.