You need a more up to date file system, such as WB 3.9's FFS or something like SFS so it can recognise bigger hard disks!
A file system alone does not help much. You need both, an updated file system and an updated IDE driver.
Also, uaehf.device is for Hard Files not hard disks!
uaehf.device is used for both, real and virtual hard drives. scsi.device does not work.
Bye,
Thomas