Are you sure the code is really being executed? You might want to put an ns_log statment in there. Also, an alternative
(since it seems the list_properties.colspec var does wind
it's way through) is to use the <list> tag to generate the
colspec.
Out of curiousity, what are you using to xform html to fo
(is it some standard xsl or something you wrote yourself)?
I have been using docbook-xsl and FOP to produce PDFs and
have been ok with the output although I see a lot of shortcomings with FOP for realistic sized documents.