Do you want to have more than one domain pointing at the same website on the same server, or pointing at different websites on the same server?
Either way, assuming you're doing it under Apache, what you want to configure is a VirtualHost. There's a RedHat tutorial
here, and if that's not right,
google provides many pointers (now that you know what you're looking for).
There is little change from Apache 1.3.x to 2.x in terms of virtualhot configuration, though (under Debian) config files did move. Assuming you're working by editing the config files, the version of RedHat it applies to is of less relevance than the version of Apache.