Dual Host / Multiple Domains mod rewrite

[bcs]

Folks, I need some help with the mod rewrite.

I have two webservers connected to a content switch (load balancer type). I have several domain names:

eg.

www.defaultdomain.com
www.newdomain1.org
www.newdomain2.net

I have the primary www.defaultdomain.com listed in the virthost as well as the machine name for internal use. My problem is I need to have this setup for the domain. When I have it on the domain virthost, the site just wont serve pages. Any ideas? Thanks in advance