I think jade only deals with sgml conversions using dsssl
stylesheets, while your docbook files seem to be xml, for
which I think only xsl stylesheets can be used.
I think XML documents that conform to the Docbook XML DTD
also happen to conform to the Docbook SGML DTD, which means
you can use DSSSL stylesheets, if you choose to. I haven't
tried converting Docbook to HTML with DSSSL, but I did convert
a whole bunch of ACS Java CMS docs (written in Docbook XML)
to RTF using OpenJade and Docbook DSSSL stylesheets.
I had to change the doctype FPI from
"-//AD//DTD DocBook XML V4.1.2-Based Extension//EN"
to "-//OASIS//DTD DocBook V4.1//EN"
