"Failed to decrypt Data must not be longer than 256 bytes" エラーが発生する理由

Issue

以下のエラーログが表示されます。このエラーを発生させないようにするにはどうしたら良いですか?
以下はエラーログの一部です。

2013-01-25 09:44:36,470 INFO  [org.ovirt.engine.core.vdsbroker.irsbroker.GetFloppyListVDSCommand] (pool-3-thread-50) FINISH, GetFloppyListVDSCommand, return:[virtio-win-1.5.3.vfd], log id: e2fbdb1
2013-01-25 09:44:36,479 INFO  [org.ovirt.engine.core.bll.IsoDomainListSyncronizer] (pool-3-thread-47) Finished automatic refresh process for ISO file type with success, for storage domain id 561542c8-bbd4-43ad-8c36-bc7facc9666d.
2013-01-25 09:44:36,483 INFO  [org.ovirt.engine.core.bll.IsoDomainListSyncronizer] (pool-3-thread-50) Finished automatic refresh process for Floppy file type with success, for storage domain id 561542c8-bbd4-43ad-8c36-bc7facc9666d.
2013-01-25 09:44:42,960 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-49) Failed to decrypt Blocktype mismatch:0
2013-01-25 09:44:42,960 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-52) Failed to decrypt Blocktype mismatch:0
2013-01-25 09:45:00,000 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-88) [298087ae] Checking autorecoverable hosts
2013-01-25 09:45:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-88) [298087ae] Autorecovering 0 hosts
2013-01-25 09:45:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-88) [298087ae] Checking autorecoverable hosts done
2013-01-25 09:45:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-88) [298087ae] Autorecovering storage domains is disabled, skipping
2013-01-25 09:46:05,315 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-82) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:46:05,315 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-59) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:46:13,560 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-89) Failed to decrypt Data must start with zero
2013-01-25 09:46:13,561 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-50) Failed to decrypt Data must start with zero
2013-01-25 09:46:30,116 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-30) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:46:30,128 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-100) Failed to decrypt Data must start with zero
2013-01-25 09:46:46,585 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-77) Failed to decrypt Data must start with zero
2013-01-25 09:46:46,585 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-66) Failed to decrypt Data must start with zero
2013-01-25 09:46:56,839 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-68) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:46:56,854 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-95) Failed to decrypt Data must start with zero
2013-01-25 09:47:03,099 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-11) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:47:03,115 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-25) Failed to decrypt Data must start with zero
2013-01-25 09:47:19,480 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-57) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:47:19,495 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-82) Failed to decrypt Data must start with zero
2013-01-25 09:47:21,621 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-90) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:47:21,621 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-40) Failed to decrypt Data must not be longer than 256 bytes
[...]
2013-01-25 09:50:00,000 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-81) [71c7b901] Checking autorecoverable hosts
2013-01-25 09:50:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-81) [71c7b901] Autorecovering 0 hosts
2013-01-25 09:50:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-81) [71c7b901] Checking autorecoverable hosts done
2013-01-25 09:50:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-81) [71c7b901] Autorecovering storage domains is disabled, skipping
2013-01-25 09:50:00,121 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-2) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:50:00,121 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-99) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:51:47,328 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-60) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:51:47,328 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-16) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:52:26,529 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-97) Failed to decrypt Data must not be longer than 256 bytes
2013-01-25 09:52:26,529 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-50) Failed to decrypt Data must not be longer than 256 bytes
[...]
2013-01-25 09:53:20,124 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-100) Failed to decrypt Data must start with zero
2013-01-25 09:53:20,124 ERROR [org.ovirt.engine.core.engineencryptutils.EncryptionUtils] (QuartzScheduler_Worker-22) Failed to decrypt Data must start with zero
(QuartzScheduler_Worker-40) Failed to decrypt Data must not be longer than2013-01-25 09:55:00,000 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-13) Checking autorecoverable hosts
2013-01-25 09:55:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-13) Autorecovering 0 hosts
2013-01-25 09:55:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-13) Checking autorecoverable hosts done
2013-01-25 09:55:00,002 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-13) Autorecovering storage domains is disabled, skipping