With Jaunty installed the RAID1 resynced without errors.
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md1 : active raid1 sda2[0] sdb2[1] 976470784 blocks [2/2] [UU]
md0 : active raid1 sda1[0] sdb1[1] 289024 blocks [2/2] [UU]
unused devices: <none>
With Jaunty installed the RAID1 resynced without errors.
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md1 : active raid1 sda2[0] sdb2[1]
976470784 blocks [2/2] [UU]
md0 : active raid1 sda1[0] sdb1[1]
289024 blocks [2/2] [UU]
unused devices: <none>