Hi, Base on some private discussion with David Chadwick, I am proposing the update to X.501 as shown in the attachment. I have done the following: a) Extended the text somewhat. Please note that I am not using the word "shall", but rather "this field is used for specifying..." ASN.1 information objects are not for implementers, but for those making specifications. b) It is added that only user attribute types are to be included. The note say that this is a little different for object classes for subentries. Erik Andersen