Rebuild a disk in RAID 1 using SCSI 320-1 Raid controller

[Vilse]

Hi!
I have one NiceLog with raid 1, unfortunately one disk is corrupt.
What i want to do is to replace the corrupt disk with a new one.

The problem is, how can i do a copy from the original disk to the new one?
I can´t rebuild the new disk since it is not in "Fail" mode.

Is it possible to set i disk into "Fail" mode manually?
Or is there other ways to to what i want?

I use MegaRaid SCSI 320-1 Raid Controller and LSI Logic PCI-X Ultra b320 SCSI- Host adapter.

Thanks for helping

/Vilse