There is no option to setup RAID 10.
But, let's get back to my previous request,
How would one setup RAID 1+0 (i.e. 2x mirror'ed RAID1's and then a RAID 0 on top of it) on say CentOS 4.6 ?
There is no option to setup RAID 10 because you are trying to create an unsupported configuration. You should separate the OS from the data area.