I have added an option to Special:Export that will add a list of all contributors of a page to the XML output. The list is distinct (each contributor mentioned only once). I also expanded the XML converter to use this. (Brion et al.: please put the new Special:Export on the live sites soon)

For my local test site, where the new Special:Export is running, it will now add a list of all contributors to the output (IPs are omitted). It will even add people who worked on a template that is used in the document ;-)

Next stop: OpenOffice .ODT output...

Magnus