No need to import built in types (possible erratum?)

In responding to a question from a user of the schema language, I couldn't
find anything in our specification that made clear that no <import> is
needed for the built-in data types.  It is clear that every schema contains
the components corresponding to those types, but the rules for a reference
to a type seem to mandate an import except when referring to the target
namespace of the schema document in which the reference appears [1].  Have
we indeed made clear that no import is needed?

[1] http://www.w3.org/TR/xmlschema-1/#src-resolve

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Noah Mendelsohn                              Voice: 1-617-693-4036
IBM Corporation                                Fax: 1-617-693-8676
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