What causes dynamic updates to be logged as fail whilst the installation has gone through in PAN-OS 5.0.8?

[edgarfc]

I have been having the system log entries below for some days and still continue after installing Application and Threats dynamic updates (3 versions) manually as well as turning off the update schedule and rebooting one of the boxes in HA mode.

2013/12/04 11:01:56 medium   general

general 0  Failed to upgrade Application identification/Threat detection package to version <unknown version>/<unknown version>

2013/12/04 11:01:56 medium   general	general 0  Content package downloaded but installation could not be scheduled
2013/12/04 11:16:05 medium   general	general 0  Failed to upgrade Application identification/Threat detection package to version <unknown version>/<unknown version>

2013/12/04 11:16:05 medium   general	general 0  Content package downloaded but installation could not be scheduled
2013/12/04 12:00:26 medium   general	general 0  Failed to upgrade Application identification/Threat detection package to version <unknown version>/<unknown version>

2013/12/04 12:00:26 medium   general	general 0  Content package downloaded but installation could not be scheduled
2013/12/04 12:30:39 medium   general	general 0  Failed to upgrade Application identification/Threat detection package to version <unknown version>/<unknown version>

2013/12/04 12:30:39 medium   general

general 0  Content package downloaded but installation could not be scheduled

Is this a system malfuction or a bug with software version 5.0.8. Version 5.0.7 work fine.