Comment 1 for bug 815760

Reproduced locally in sbuild environment; a bit more information on the failure:

xsltproc --stringparam callout.graphics 0 --stringparam navig.graphics 0 --stringparam admon.textlabel 1 --stringparam admon.graphics 0 --stringparam base.dir user-manual.chunked/ /etc/asciidoc/docbook-xsl/chunked.xsl /build/jamespage-nut_2.6.1-2ubuntu1-i386-VnuJ0Q/nut-2.6.1/docs/user-manual.xml
warning: failed to load external entity "http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"
compilation error: file http://docbook.sourceforge.net/release/xsl/current/xhtml/chunk.xsl line 25 element import
xsl:import : unable to load http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl