>>>>> "Michael" == Michael Kay <mike@xxxxxxxxxxxx> writes:

    Michael> In other words: it might not be a URI that conforms to
    Michael> the rules of the file URI scheme, but there is nothing in
    Michael> the XSLT/XPath specs that says it should be.

I agree with both those statements. 

It is still non-conformant, and I don't think you should do this.

Of course, the W3C are about to give you ample room to argue otherwise.
-- 
Colin Adams
Preston Lancashire