RHEL5 and problems with cryptsetup luksOpen

I just did an "yum update" and now I cannot access my encrypted disk. As
this is Red Hat Enterprise I must say I doubt that this is an error in the
distribution and maybe the error is a faulty password or alike but I need to
toss this in the air and see what happens as I have no other ideas as I have
entered this password countless number of times previously.

This is what I do.

[root@srv]# cryptsetup luksOpen /dev/sdc maxtor250
Enter LUKS passphrase for /dev/sdc:
Enter LUKS passphrase for /dev/sdc:
Enter LUKS passphrase for /dev/sdc:
Command failed: No key available with this passphrase.

/var/log/messages:
Sep 26 17:27:52 ns yum: Updated: cryptsetup-luks-1.0.3-5.el5.i386

[root@srv]# cryptsetup luksUUID /dev/sdc
ab33d9d8-9257-472f-a699-fbb946827e18

[root@srv]# cryptsetup isLuks /dev/sdc

[root@srv]# cryptsetup isLuks /dev/sda
/dev/sda is not a LUKS partition

[root@srv]# cryptsetup isLuks /dev/sdb
/dev/sdb is not a LUKS partition

Do note that it doesn't write anything for the /dev/sdc device!? Shouldn't
it write that this is a Luks device?

man cryptsetup:
isLuks <device>
returns true, if <device> is a LUKS partition. Otherwise, false. No
options.

[root@srv]# cryptsetup luksDump /dev/sdc
LUKS header information for /dev/sdc

Version: 1
Cipher name: aes
Cipher mode: cbc-essiv:sha256
Hash spec: sha1
Payload offset: 1032
MK bits: 128
MK digest: 00 be b6 ba 35 95 e9 4e 59 92 bb 42 1a 45 44 4b 2e d8 1e 75
MK salt: f5 ba 56 20 2c 86 4f 76 3e 6a 65 98 0a 67 f8 4b
5c c4 0a 7e df 82 79 84 2f 2e ed 8b 5e 11 db 64
MK iterations: 10
UUID: ab33d9d8-9257-472f-a699-fbb946827e19

Key Slot 0: ENABLED
Iterations: 64318
Salt: a8 2b 17 c6 99 03 55 e8 01 e0 f4 5e 42 2d 8a
6a
9f 3e 39 db 4b 0c 29 7f 11 60 36 ea 59 37 5f
51
Key material offset: 8
AF stripes: 4000
Key Slot 1: DISABLED
Key Slot 2: DISABLED
Key Slot 3: DISABLED
Key Slot 4: DISABLED
Key Slot 5: DISABLED
Key Slot 6: DISABLED
Key Slot 7: DISABLED

tail /var/log/dmesg:
device-mapper: multipath: version 1.0.5 loaded
Vendor: Maxtor Model: OneTouch II Rev: 023g
Type: Direct-Access ANSI SCSI revision: 04
SCSI device sdc: 490234752 512-byte hdwr sectors (251000 MB)
sdc: Write Protect is off
sdc: Mode Sense: 24 00 00 00
sdc: assuming drive cache: write through
SCSI device sdc: 490234752 512-byte hdwr sectors (251000 MB)
sdc: Write Protect is off
sdc: Mode Sense: 24 00 00 00
sdc: assuming drive cache: write through
sdc: unknown partition table
sd 2:0:0:0: Attached scsi disk sdc
sd 2:0:0:0: Attached scsi generic sg2 type 0
usb-storage: device scan complete
EXT3 FS on dm-0, internal journal

Has anyone else experienced anything like it or is this some kind of
brain-freeze that I have forgotten my password? Naturally I do not need to
say that there is vital (for me) personal data on that disk - the best part
is that my backup is residing on another RHEL5 server... and on another
encrypted partition... with the exact same error so at least the "problem"
is identical! (geee) I updated both servers at the same time.