The 2.4.2-2 kernel IDE code pokes at supertrak slave controllers without due care and attention. The result of this is to seriously annoy the i910 i2o processor managing the devices causing a very annoying raid rebuild and hanging the boot [Temporary workaround hde=noprobe hdg=noprobe hdi=noprobe sort of works, at least well enough to replace the kernel] The chips are marked as raid controller, bios disable so the ide code has no business poking its nose in
Fixed in current -ac