corrupted 600GiB md device

Hello,

I'm trying to create a soft RAID device from a remote LVM logical volume imported via iscsi and another, local logical volume. It works without issue most of the time, but I've found that if I specify a 600GiB partition with lvcreate, such as with 'lvcreate -L 600G -n test1 LVM' that /dev/md0 is "corrupted" until the device finishes syncing. For example, 'fsck /dev/md0'

fsck 1.39 (29-May-2006)
e2fsck 1.39 (29-May-2006)
The filesystem size (according to the superblock) is 157286400 blocks The physical size of the device is 157286384 blocks
Either the superblock or the partition table is likely to be corrupt!

And the details of the array:

/dev/md0:

        Version : 0.90

Creation Time : Mon Mar 28 20:56:00 2011
Raid Level : raid1
Array Size : 629145536 (600.00 GiB 644.25 GB)
Used Dev Size : 629145536 (600.00 GiB 644.25 GB)
Raid Devices : 2
Total Devices : 2
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Mon Mar 28 20:56:34 2011
State : active, resyncing
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0

Rebuild Status : 0% complete

UUID : da6c0776:2f3beb8f:b13b8b58:8282847d
Events : 0.3

Number Major Minor RaidDevice State
0 8 32 0 active sync /dev/sdc
1 253 10 1 active sync /dev/LVM/npgtest1

With RAID 1.0 metadata, fsck returns the same error, though the size of the physical device varies from the filesystem by 34 blocks instead of 16. With 1.1 and 1.2 metadata, I get the following error instead:

Couldn't find ext2 superblock, trying backup blocks... fsck.ext2: Bad magic number in super-block while trying to open /dev/md0

I seem to only have this problem when specifying a logical volume of 600GiB. If I shrink the filesystem on the original volume (before exporting it via iscsi) slightly, I can't reproduce this. Am I seeing intended behavior? If so, what would be the appropriate way to work around it?

-Nathan