Installing multisite network admin on sub-domain

I was searching the Net and also playing around WordPress to achieve my desired multisite installation, but I wasn’t successful yet. What I want to do is to have the network admin site installed on a sub-domain like www.example.com (not example.com) and other sites in the network on sub-domains like client.example.com (not client.www.example.com).

Is there any way to make it possible!?

Important Note: I want to map example.com to a different server with different IP than www.example.com and the rest of sites. Also, I don’t want to map each sub site address by hand. I want it to be automatic.

Server specification: I use nginx + php-fpm + fastcgi + centos 5.9.

Yes. Here are the instructions:

1. Install and configure WP for www.example.com
2. Configure multisite – can use either sub-domain or sub-directory
3. Install WP Domain Mapping plugin – http://wordpress.org/plugins/wordpress-mu-domain-mapping/
4. Create new site, e.g. site1
5. Using Domain Mapping plugin, map site (site1.www.example.com or www.example.com/site1) to preferred sitename (site1.example.com)

I actually have two separate WP sites setup as above, one is sub-domain and another sub-directory. One of the sites is hosting 200 different hostnames. The other is in development and only setup for two hostnames.