The note says: "If you are not creating a RAID partition of /boot, and you are making a RAID partition of /, it must be RAID level 1 and it must use one of the first two drives (IDE first, SCSI second)." IMHO it should read: "If you are not creating a separate partition of /boot, and you are making a RAID partition of / ..."
Thanks so much! This has been added to the RHEL4 documentation, which should be released around the Update 1 timeframe. Thanks so much! :-)