In order to select which cert to present you would need to have access to the HTTP host header in the client request. In order to inspect the HTTP content in a request, you'd need to have already have presented the SSL certificate.
In short, you either need to have a separate IP:port available for each unique SSL FQDN or you need a wildcard cert that matches the domain or subdomains of all FQDN's you want the VIP to answer for.
So if you have a few sites with the following FQDN's:
a.b.c.mydomain.com
x.y.z.mydomain.com
You would need a wildcard cert for *.mydomain.com. If a part of the subdomain's matched, you could get a more specific wildcard cert. For example, *.c.mydomain.com would work for these two FQDN's:
a.b.c.mydomain.com
x.y.c.mydomain.com
Hope this helps,
Aaron