In section 1.3.0.1 (Enhanced font support) of the
installation guide (I am looking at the electronic version
from the rhl-install-guide-en-6.0-2 rpm) you give
instructions for using the new font server instead of a
conventional fontpath.
Those direction say to use "tcp/localhost:7100" in the
fontpath.  However, the version of xfs in
XFree86-xfs-3.3.3.1-49 has intentionally had TCP
functionality removed (XFree86-3.3.3.1-xfsredhat.patch
modification of file
XFree86-3.3.3.1/xc/programs/xfs/os/connection.c).  The
correct instruction would be to use "unix/:-1" in the
fontpath.