In our openfire server, we have different groups. We create users and assign users into different groups as per our requirement. The automatic Inband account registration is disabled. Contact list (Roster) sharing is done in Group basis. Suppose we have a group X and its contact list is shared with group Y and not with group Z. Also suppose we have a user SCOTT who is member of group X, he could see the members of group Y but should not see the members of group Z. As per our group sharing it is working fine. But what the user SCOTT is doing he is manually adding user TIGER (who is a member of group Z) into his list and this is what we do not want. No user of group Z should be available to the users of group X. How we can restrict the user SCOTT to add users of other group (which is not visible to his group) manually? Kindly help.