I used to get them here:
http://xdxf.revdanica.com/down/[
^], but now this resource is closed. Probably you can find the ends, maybe in Fluentizer or somewhere. I do have some of the copies and the software of my own.
By the way, this is a very interesting and more or less comprehensive standard. Please see:
http://en.wikipedia.org/wiki/Xdxf[
^],
http://xdxf.revdanica.com/[
^].
You can look for applications (see the links above); may be they package some dictionaries with downloadable packages, ask on their forums.
—SA