What I am doing is something a bit more complicated but it's really good (IMHO)
.- Any request on Port 8443 under ssl for control panel
.- Port 443 for customers ssl
.- Port 80 for non-ssl sites.
This alltogether with some rewirte magic, allows me to redirect all 443 and 80 requests for the main vhost, to the 8443 port where it is listening.
So I am telling the customers to access via
https://theirdomain.com:8443 but they end up getting redirected to
https://mydomain.com:8443 (and so, with a single certificate, I can have a secure page for everyone)