xpath/c14n1[01] testcase

Assume a source document like this:
        <foo xml:id='x'>
                <bar>
                        <subset>
                                ....
                        </subset>
                </bar>
        </foo>

1. Sign this with an XPath transform that picks the subset.
Someone who can verify the signature must be using c14n 1.0; if the 
signature doesn't verify something's broken.

2. Modify the source document so that the xml:id now appears on the 'bar' 
element and verify the signature.
We expect the same results as #1 and have the additional property that we 
can show how c14n 1.0 is insecure :)

#3. Modify the source document so that the xml:id now appears on the 
subset element.
The behavior of 1.0 is unchanged, the behavior of 1.1 depends on the XPath 
expression (whether subset's attributes are included or not)

Hmm, now that I write it down this still seems interesting, but perhaps 
not as pragmatically useful as I first thought.
        /r$

--
STSM
Senior Security Architect
DataPower SOA Appliances