Apache has their own support for virtual domains. This is the only program I recommend using the internal virtual domain mechanism. When you run something through inetd there is a cost. The program now has to start up each time you run it. That means slower response times which is unacceptable for web service. Apache also has a mechanism for stopping connections when too many come in.
However, if you did want to run Apache through inetd then add the following line to your inetd.conf file:
www stream tcp nowait www /usr/bin/virtuald virtuald /virtual/conf.www httpd -f /var/www/conf/httpd.conf
In the /var/www/conf/httpd.conf file you have to specify:
Then configure each instance of the Apache server like you would normally for single domain use.
At the time of this writing there is no virtual web HOWTO. However, I am under the impression one is coming. Eventually I will just refer to that HOWTO and have some notes on it. If it does not come soon and I get enough requests I will write a small section on how to configure the Apache virthost directive.