It appears there is a looping symlink in the centos/4 directory, as shown here: # ls -l /mirror/centos/4/HEADER.images/ total 24 -rw-rw-r-- 2 distro distro 4734 Apr 19 22:00 centos_icon_60.png -rw-rw-r-- 2 distro distro 14815 Apr 19 22:00 centos_logo_45.png lrwxrwxrwx 1 distro distro 14 Sep 27 22:01 HEADER.html -> ../HEADER.html lrwxrwxrwx 1 distro distro 16 Sep 27 22:01 HEADER.images -> ../HEADER.images
You can see this on other mirrors as well: http://centos.cs.ucr.edu/centos/4/HEADER.images/HEADER.images/HEADER.images/
-Doug