"namespace xsd" is not really working

The namespace xsd statement can be used to put namespace declarations into the xsd. So far, so expected,. What makes it a problem is the fact, that normal languages need an identifier here. In that regard, XSD is different, because this should be possible to do this:

<?xml version="1.0" encoding="UTF-8" ?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://example.com" xmlns="http://example.com" elementFormDefault="qualified">

    <!-- ... stuff ... -->

</xsd:schema>

However, there is no way to express this in the IDL. The foillowing leads to an syntax error, because the value is expected to be an identifier even for xsd.

namespace xsd "http://example.com"