I have a following problem with updating ZCM to 10.2.1:

About half of our workstations and ZEN server itself cannot install update to ZCM 10.2.1. Whenever I try to view workstation/server information I get the following error:

Novell ZENworks Control Center has encountered an error. The details of the error are shown below.

Error Details:
at com.novell.zenworks.datamodel.services.systemupdat e.

(the whole message in the attached text file)

Now, when I check ZENworks server itself, I got a message that the update failed:

This device was unable to rebuild the deployment packages. Check the loader-messages.log on the device for more details.

Loader-message.log is there, but contains more than 8 MB of text.

Any ideas anyone?
Thanks a lot for any input!