Create or change of a User Diretory in the SiteMinder AdminUI SP7 and SP8 is not possible and this operation leads to the error message:
Failed to execute ModifyUserDirectoryEvent.
ERROR MESSAGE: SmApiWrappedException:Class
CA.SM::UserDirectory does not have attribute
Apply the full steps from the documentation (1), and once this has been done, User Directories creation and modification will work as expected and this will solve the error seen in the AdminUI.