19 June 2000 Backwards-incompatible changes to DocBook that are planned for V5.0: - DocBook V5.0 will be an XML DTD. This will require a wide range of changes. As a result, DocBook V5.0 will more closely resemble The XML version of DocBook V4.1 than the SGML version. - Parameter entity reorganization may greatly reduce many content models. The goal of this effort is to remove a large number of spurious elements that snuck into content models during the first PE reorg, in practice these changes should have very little "real world" impact. - The Coords attribute will be removed from AreaSet. - ArtHeader will be dropped from BiblioEntry - Contents attribute will be removed from BookInfo and SetInfo - The %indexdivcomponent.mix; will be restricted. Numbered figures and other elements inappropriate for an Index or SetIndex will be removed. - RevHistory will be removed from GlossTerm - Constant Class will be removed from SystemItem - Graphic and InlineGraphic will be removed - Tables will be restricted from full CALS to the OASIS Exchange model - An experimental XML Schema version of DocBook 5.0 will be produced in parallel with the DTD version. It will be backwards-incompatible in an unspecified number of ways. The goal of the effort will be that most DocBook documents that validate under the DTD will also validate under the Schema, but the committee does not feel bound to guarantee this condition.