Hi Chris,
That message means the Java extension that gets the filename of the
document being processed is not available, probably because you aren't
using Saxon or Xalan. It was added in 1.71.1.
If all you are doing is converting a DocBook5 document to Docbook4
(although your mail said "to DocBook 5"), then it doesn't matter. It only
matters for the node-set being processed internally by the DocBook4
stylesheet, because otherwise it could not resolve paths relative to the
document file (since it is processing a node-set in memory, not a document
file).
Bob Stayton
Sagehill Enterprises
DocBook Consulting
bobs@sagehill.net