I got mwdumper to work, but IMHO it still a very broken utility. I worked on it for some time and discovered the voodoo sequence on Linux to get it working. I went ahead and was bold and updated the meta pages with some useful advice for others who run into these problems. As I previously suggested, I think it would be a good idea to improve the quality of these tools since they do not work properly with released MediaWiki Distributions and published XML dumps provide from Wikipedia with A LOT of work and debugging.
I have updated meta here:
http://meta.wikimedia.org/wiki/Data_dumps
Jeff