CNAME question

I have a question about setting up a vhost to pick up the sub-domains.

I do have this working, but it will only work on the domain that the IP in the virtual host is pointing to.

For example, I set up and it all worked fine. For the domain, I put in the following dns info:


That worked great, but when I did the same with, it would go through the signup process fine, but when I clicked on the link in the email, it would go to the site.

I admit, I know little about DNS, and only got to that CNAME info by looking through Google and guessing (my style of discovery).

Can anybody tell me what I should actually do and what settings to have?

I'm using Plesk control panel.