RAID dead drive? raidtools-1.00.3-2.i386

[analyst.3852505 at bloglines.com (analyst.3852505 at bloglines.com)]

Hi,

  I seem to have a drive that was setup as part of a two-disk software
RAID mirror that current displays as the following, using lsraid:

[dev
  9,   0] /dev/md0         50682BC2.AE9F5709.D6FF8767.D6946564 online
[dev
 22,   1] /dev/hdc1        50682BC2.AE9F5709.D6FF8767.D6946564 good
[dev
  ?,   ?] (unknown)        00000000.00000000.00000000.00000000 missing

I think the second drive, /dev/hdd1, is dead, or hurting and should be replaced.
 What I'm looking for, is guidance, in replacing the drive - ie., commands
/ steps to remove dead drive and have replacement resume the mirror.

Using
raidtools-1.00.3-2.i386.

Any help would be appreciated.

Tony Koker