I'm trying to port some DocBook builds from Saxon to the JDK's bundled
XSLTC to reduce the dependency footprint and build requirements. These
are fairly straight-forward DocBook documents and the 1.79.2 XSLT 1.0
stylesheets for same. It all worked reasonably well with Saxon 6.5.
With the JDK implementation it fails like this:

Caused by: java.lang.NullPointerException
     at

com.sun.org.apache.xalan.internal.xsltc.runtime.BasisLibrary.referenceToNodeS
et(BasisLibrary.java:1024)

     at docbook.l10n$dot$language()
     at docbook.topLevel()
     at docbook.transform()
     at

com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet.transform(Ab
stractTranslet.java:624)

at

com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Transf
ormerImpl.java:732)

at

com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Transf
ormerImpl.java:345)

... 3 more

Does this look familiar to anyone? Is anyone using the JDK XSLT engine
with DocBook?

Is docbook.transform() code you wrote to run the Docbook stylesheets? Or
is that somehow part of the Docbook distribution?