[relaxng-user] customization layers in rnc?

[Bruce D'Arcus]

Can someone please help me understand how to implement the following  
customization layer for the DocBook DTD in RNC?

Simply running Trang on it gets me the following error:

	dbcitx.dtd:21:67: fatal: syntax error

Bruce
------------------------------------------------------------------------ 
---------------------------------
<!-- This is a customization layer for DocBook XML 4.1.2 which  
implements
      RFE 810932 - improved citation support -->

<!ENTITY % citation.module "IGNORE">
<!ENTITY % citation.element "IGNORE">
<!ENTITY % citation.attlist "IGNORE">

<!ENTITY % blockquote.module "IGNORE">
<!ENTITY % blockquote.element "IGNORE">
<!ENTITY % blockquote.attlist "IGNORE">

<!ENTITY % quote.module "IGNORE">
<!ENTITY % quote.element "IGNORE">
<!ENTITY % quote.attlist "IGNORE">

<!ENTITY % epigraph.module "IGNORE">
<!ENTITY % epigraph.element "IGNORE">
<!ENTITY % epigraph.attlist "IGNORE">

<!-- load original DocBook stuff -->
<!ENTITY % DocBookDTD PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN">
%DocBookDTD;

<!-- extend the citation element.
      we add two attributes: renderas (select the processing  
expectations)
                             caption (provide additional text)
      we add one element:    Biblioref (extended bibliographic data)
-->

<!ENTITY % local.citation.attrib "">
<!ENTITY % citation.role.attrib "%role.attrib;">

<!ELEMENT biblioref - - EMPTY>
<!ATTLIST biblioref linkend IDREF #IMPLIED
                         endterm IDREF #IMPLIED
                         unit NMTOKEN #IMPLIED
                         start NMTOKEN #IMPLIED
                         stop NMTOKEN #IMPLIED
>

<!ELEMENT citation - - ((%para.char.mix;|biblioref)+)>

<!ATTLIST citation
                 %common.attrib;
                 %citation.role.attrib;
                 %local.citation.attrib;
                 renderas (full|author|year|title) "full"
                 caption CDATA #IMPLIED
>

<!-- done with the citation element -->

<!-- extend the blockquote element -->
<!ENTITY % local.blockquote.attrib "">
<!ENTITY % blockquote.role.attrib "%role.attrib;">

<!ELEMENT blockquote - - (title?, attribution?, (%component.mix;)+,  
biblioref?)>

<!ATTLIST blockquote
                 %common.attrib;
                 %blockquote.role.attrib;
                 %local.blockquote.attrib;
>

<!-- done with blockquote -->

<!-- extend the quote element -->
<!ENTITY % local.quote.attrib "">
<!ENTITY % quote.role.attrib "%role.attrib;">

<!ELEMENT quote - - ((%para.char.mix;)+, biblioref?)>

<!ATTLIST quote
                 %common.attrib;
                 %quote.role.attrib;
                 %local.quote.attrib;
>

<!-- done with quote -->

<!-- extend the epigraph element -->
<!ENTITY % local.epigraph.attrib "">
<!ENTITY % epigraph.role.attrib "%role.attrib;">

<!ELEMENT epigraph - - (attribution?, (%para.class;)+, biblioref?)>

<!ATTLIST epigraph
                 %common.attrib;
                 %epigraph.role.attrib;
                 %local.epigraph.attrib;
>
<!-- done with epigraph -->