11/7    A lot of XML documents contain things like:
        xmlns:xi="http://www.w3.org/2001/XInclude"
        Isn't it bad practice to have an IT infrastructure depend on a
        resource hosted on a machine that may have down-time?
        \_ That's not a "real" URL, it's what's called a URN.  Basically it's
           just a unique string to say "this is the unique namespace which 'xi'
           will be an abbreviation for."  Common convention is that it point at
           the DTD or something that links to the DTD, but in general that
           URL is never actually fetched.  --dbushong
           \_ I say this because I have a document that is dependent on
              files hosted on http://docbook.sourceforge.net I didn't
              notice that the site had gone down until I looked at the
              stylesheet I was using and realized why xsltproc was hanging.
              \_ Ah, that's different.  That's <?xml-stylesheet, which DOES
                 require that it be fetched.  You should definitely have a
                 local copy of those referenced.  --dbushong