[XPath30] question about URIQualifiedName

Hi all,
    XPath 3.0 seems to have introduced the following new "XML name" syntax,

EQName                  ::=    QName | URIQualifiedName
URIQualifiedName   ::=    BracedURILiteral NCName
BracedURILiteral      ::=    "Q" "{" [^{}]* "}"

The URIQualifiedName seems to be new in XPath 3.0. What was the reason of
introducing this? I feel, that QName is all that is needed.



-- 
Regards,
Mukul Gandhi