DOCBOOK-APPS: <textdata/> --> use of URI's in fileref?

Hi all,

Would it be "incorrect" -- in terms of the "DocBook content model" -- to use URI's in the "fileref" attribute of <textdata/> ?

An example use case for this is the documentation of a DocBook customization: I wanted to add the source code of the customization layer into my output, and my first thought was, to specify the DTD's Public ID as "fileref" in <textdata/> to _automagically_ include it in the output:

<programlisting>
  <textobject>
    <textdata fileref="-//DSPFACTORY//DTD DocBook XInclude Module V1.0//EN"/>
  </textobject>
</programlisting>

However, the <insertfile/> extension element did not resolve this; and so I asked myself if I was about to mis-use resolving in a place were it was not right to use it [ it was a "fileref" and not a "href" ]
Any comments on this?

Note: 
I'm thinking about modifying the JAVA extension locally, using Norm's Catalog Resolver -- or the Stylesheet processor's own Resolver --, but on the other hand, it could be of general use, that URI's could be used in <textdata /> ... 
 
Regards,
Johann

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Johann Richard
IC & DSP Design Engineer  
Dspfactory SA
Champs-Montants 12a 
2074 Marin-Epagnier
Switzerland

Tel: +41 32 755 7462 
Fax: +41 32 755 7401 
e-mail: mailto:

http://www.dspfactory.com
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