I have a patch that makes everything pass xmlwf and xmllint. It was generated by running tidy on all the files that did not validate.
However, monodoc still complains about some files when it is running. An example is html/en/installation/linux.html. If anyone can figure that one out it would be great. I checked the file, it looks alright to me. To compile, you need the patches I just checked in to monodoc.
monkeyvalid.patch.bz2
Description: application/bzip
