Policy has been deleted

I added a new policy document in a domino directory on a 8.0.2 server using a 8.5.1 client. Accordingly a added a policy settings document for Mail. So far everything is fine - when i open the policy document i could click on the click for the settings document and will be directed to it. When i open the policy document in a replica of the domino directory on a second server the entry for the mail setting is replaced by . When i have a look into the document properties of that policy document in the policies view i could fined a valid DocumentUNID in the field MailSets. When i do the same when the policy document is opened the field MailSets is empty.

Any ideas how to solve that problem?