PROBLEM DESCRIPTION: RedhatEnterprise RC1 does not give the option to manually install X windows. In order be able to use the GUI after the installation, you must select the "Everything" option during the package selection screen. Otherwise, it will stay in text mode.
This sounds like a comps file problem.
this is by-design (targetting the server for headless operations). 6.2.2 (EE HA) also had the same behavior.