Multisite SSL not working

Hi,
I have a multisite setup called http://www.multisite.com and i have many subsites called site1.multisite.com, site2.multisite.com, site3.multisite.com etc;

For ssl I have a wildcard ssl covering all subdomain based website and its configured to the virtual host
<VirtualHost *:443>
ServerAdmin webmaster@localhost
ServerName multisite.com
DocumentRoot /var/www/html

We have mapped an external doman http://www.somedomain.com to site2.multisite.com

How do we configure an SSL for http://www.somedomain.com . Need help to configure ssl for a specific domain under a domain mapped multisite setup. Kindly guide. Thanks