Why does Red Hat Enterprise Linux 4 fail to install GRUB at the end of an otherwise successful installation when installed on I2O block arrays?

Release Found: Red Hat Enterprise Linux 4, Red Hat Enterprise Linux 4 Update 1

Symptom:

I2O controllers comprise many different SCSI and rarer Integrated Development Environment (IDE). RAID controllers supported by the i2o_block driver. The most prevalent of these are Adaptec or DPT branded, but several other brands and models are av...