Hello,     
     
When reading section "B.1 Type Promotion" in the working draft of the 4th     
April,[1] one find the following note-paragraph:     
     
Since xs:anyURI values can be promoted to xs:string, functions and operators     
that compare strings using the default collation also compare xs:URI values     
using the default collation. This ensures that orderings that include strings,     
xs:URI values, or any combination of the two types are consistent and     
well-defined.     
     
Suggestively, is two data types referred to, "xs:URI" and "xs:anyURI". From     
what I know, there is no W3C XML Schema data type in the schema namespace named     
"URI", and I think "xs:URI" is a typo for "xs:anyURI".     
    
Now assuming it is a typo, I cannot tell how widespread this error is. Perhaps    
searching in appropriate documents, such as those which have been edited by the 
person who wrote the paragraph, would be a good idea.    
  
(Perhaps grepping for "xs:" and reviewing all data type names for typos would  
find more errors.)  
  
    
Cheers,     
Frans     
     
1.     
http://www.w3.org/TR/2005/WD-xpath20-20050404/#promotion