It took me a lot of hours of work, but I got all the files on my homesite (including those that were not directly accessible), to validate as valid HTML or XHTML. This is in continuation to this entry. Using a customised version of the WDG validator that I installed on the localhost, I was able to find all the errors and warnings, as well as fix many broken links, etc. It took a lot of work of tweaking HTML, fixing broken links, adding DOCTYPE's and sometimes fixing the tools that generated bad HTML.
Like I said, it took a lot of work, but now I feel both accomplished and relieved. The validator reports a few errors for the DocBook/XML files because it cannot find their DTD, but that's it. Now I'd better start doing something more important... ;-).