I just upgraded a system from 11.2 milestone 8 to 11.2 RC1; I now cannot boot. My drive is encrypted. Error:

Enter LUKS Passphrase:

device-mapper: table: 253:0: crypt: unknown target type
device-mapper: ioctl: error adding target to table
device-mapper: ioctl: devices doesn't appear to be in the dev hash table.
Command failed: Failed to setup dm-crypt key mapping for device /dev/sda2.
Check that kernel supports aes-cbc-essiv:sha256 cipher (check syslog for more info)

Of course, as I can't get onto the drive, I can't even check the kernel and try to create a new initrd...
Any suggestions?

System is a laptop - HP/Compaq 8510p, Core2 Duo 7500, 4GB