Comments on draft-ietf-xmldsig-xpf2-00.txt

[hardie@qualcomm.com]

While I understand that this is re-publicaton  of a W3C draft, I believe
that an explicit reference to the W3C errata for the XPATH specification
is warranted, as I do not believe that those used to the IETF citation
style will know to look for it.   In this particular case, there are 
clarifications
that result in pointers to conditions known to impact interoperability.

See for example Section 5:

Section 5

The treatment of namespace names that are relative URIs is 
implementation-dependent, in accordance with the W3C XML Plenary 
decision .

Replace:
The namespace URI specified in the XML document can be a URI 
reference as defined in [RFC2396] ; this means it can have a fragment 
identifier and can be relative. A relative URI should be resolved 
into an absolute URI during namespace processing: the namespace URIs 
of expanded-name s of nodes in the data model should be absolute.

with:
Anamespace name specified in a namespace declaration in an XML 
document is a URI reference as defined in [RFC2396] ; this implies it 
can have a fragment identifier and can be relative. The namespace URI 
component of an expanded-name is implementation-dependent if the 
expanded-name is expanded from a QName whose prefix is declared by a 
namespace declaration with a namespace name that is a relative URI 
(with or without a fragment identifier).  An XPath expression that 
depends on the value of the namespace URI component of such 
expanded-name s is not interoperable.

Similarly in section 5.4 , replace:
The string-value of a namespace node is the namespace URI that is 
being bound to the namespace prefix; if it is relative, it must be 
resolved just like a namespace URI in an expanded-name .

with:
The string-value of a namespace node is the namespace URI that is 
being bound to the namespace prefix; if the namespace name occurring 
in the namespace declaration in the XML document is a relative URI 
(with or without a fragment identifier), then the string-value is 
implementation-dependent.  An XPath expression that depends on the 
string-value of such namespace nodes is not interoperable.