Ugh.
Reinstall it with Linux or OpenSolaris and just run it as a shared hosting machine. A single IP on the physical host won't allow for incoming connections to be sent to the proper host unless you run some seriously fucked up setup where anything going to the IP is passed off to a reverse proxy running on the physical host which will then use the local host file/configs to fetch it off the httpd running on the virtual server.
I'd not run it the way you described
