By default, Red Hat distributions install a package called vim-minimal. This is a stripped down version of Vim that does not contain some of the more advanced features such as syntax highlighting. To get the full version of the editor install the packages:

vim-X11-<version>.i386.rpm<\n>
vim-common-<version>.i386.rpm
vim-enhanced-<version>.i386.rpm
(<version> is the version number of the Vim that
comes with your system.)