SSL Support with Different Domains

We're hosting sites for several clients and ideally would like to use Domain Access. There will be a considerable amount of shared content so it would certainly make things easy. Some of the content must use SSL. Additionally, there will be multiple domains (e.g. company.com, example.com, another.com).

Hosting is at Media Temple on a DV server. Obviously all of the domains would be using a shared IP address.

I'm trying to figure out how I can make this work on the SSL side. I don't see how a standard certificate can work since it requires one domain per IP. I don't think Wildcard SSLs work in this case since there are different domains, not just subdomains. Perhaps something like GeoTrust Multi-Domain SSL would work. If necessary I can have the SSL content on a subdomain so www.example.com is non-SSL and secure.example.com is SSL.

Another question is about choosing the base URL in Domain Access (I believe that's the option - http:// or https://). Does that mean the entire domain needs to be EITHER http:// or https://? We can't use SSL for some but not others?

Thanks.