I just made few changes in odt2html: implement
  a) PreformatettedText style ( <pre> environment in html)
  b) Programmlisting DOCBOOK style (according to Docbook template, supplied with OO).
insert-spaces template now really insert spaces.

File is attached to this message, I will be happy see one in next version of odftools.
URL is http://opendocumentfellowship.com/files/odt2html.xsl.tgz