The DFDL spec is very restrictive about the use of %ES; - it is only permitted as a nil literal value. But the spec does not say anything about the use of %WSP*; when used on its own - which may equivalently be written as "%ES; %WSP+;". I don't think that %WSP*; should be allowed on its own other than for nil literal value. It may of course be used in combination with other DFDL entities. Regards Steve Hanson Architect, Data Format Description Language (DFDL) Co-Chair, OGF DFDL Working Group IBM SWG, Hursley, UK smh@uk.ibm.com tel:+44-1962-815848 Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU