The new raidtools (0.90) used in RH 6.0 do not contain
raidadd and raidrun any longer. However, there are still
calls to these programs in rc.sysinit:

if [ -f /proc/mdstat -a -f /etc/raidtab -a -x /sbin/raidadd
]; then
	action "Starting up RAID devices" raidadd -a
	rc=$?

	if [ $rc = 0 ]; then
		raidrun -a
		rc=$?
	fi
	(...)


In order to make the script work this should be changed to
the following:

if [ -f /proc/mdstat -a -f /etc/raidtab -a -x
/sbin/raidstart ]; then
	action "Starting up RAID devices" raidstart --all
	rc=$?
	(...)