Very confusing message for err:XQST0045

Query:
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declare function foo() {
};
1
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Error:
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<d:\mm.xq>:1,9: static error [err:XQST0045]: "foo": invalid function or annotation namespace; raised at zorba\src\compiler\translator\translator.cpp:31 26
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It took me a few minutes to determine what is wrong on this query based on the error message.

Spec:
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err:XQST0045
It is a static error if the function name in a function declaration is in one of the following namespaces:
  http://www.w3.org/XML/1998/namespace,
  http://www.w3.org/2001/XMLSchema,
  http://www.w3.org/2001/XMLSchema-instance,
  http://www.w3.org/2005/xpath-functions,
  http://www.w3.org/2005/xpath-functions/math.
--------------------------------
.

So, indeed, the function "foo" is declared in the default namespace. That is http://www.w3.org/2005/xpath-functions is no default namespace declaration is present.

But the error message says:
  "foo": invalid function or annotation namespace

With only that [almost] everybody understands that the "foo" is the wrong "function namespace".

Therefore the understandable error message would be:
  function "foo" is declared in a reserved namespace: http://www.w3.org/2005/xpath-functions/math"

That would make this error's general message look like:
  %1 "%2" is declared in a reserved namespace: %3.%4"

%1 - annotation/function
%2 - QName
%3 - URI (*only* one of the err:XQST0045 list)
%4 - optional advice!!!

Fore more user friendliness, PLEASE also add %4. If in main module and default function namespace is fn, %4 is:
 ' Use "local:foo".'