[Michael Kay]

Contrary to the specification, Saxon requires the href
attribute of xsl:result-document to identify a URI that
is strictly legal according to the RFC 2396 syntax. The
specification also allows a string that can be turned
into a valid RFC 2396 URI by escaping special
characters (such as spaces).

Thus Saxon currently allows

href="file:///c:/My%20Documents/out.html"

but under the spec it should also allow

href="file:///c:/My Documents/out.html"

Test case added: mdocs33