I had a
similar bug on i386 Debian 4.0 r1 and 2x2 raid1 disks
In /etc/fstab /boot was assigned as /dev/sdb1 which is part of my lvm volume
(/dev/sda2 + /dev/sdb1). But it should have been /dev/sda1 which was the real
/boot partition.
So fsck tried to check sdb1 and failed.
After changing /dev/sdb1 into /dev/sda1 in /etc/fstab everything was working as
expected.