Originally Posted by martinfst
I think you ask two questions.
1. One Cert for multiple domains: this is not possible because of the way ssl is working. SSL Certs work for one domain and one IP. There is a special case for wildcard certs, which will allow multiple system hostnames to authenticate with the same Cert, but that's the only exception.
I think i have to give you an example on what i mean with one cert for multiple domains.
Let's think about a server that has the following hostname "server1.mydomain.com". server1.mydomain.com also exists as a valid dns A-record.
So you now create a cert for "server1.mydomain.com". Then you have to configure apache to use name-based virtual hosts for <yourip>:443 like in the following example:
Maybe calling that "one cert for multiple domains" has been confusing, but the above configuration is definitely working and valid. Plesk, for example, supports that kind of apache configuration. I think it's the default behaviour until you upload or create your own cert.