The rnc schema is not compatible with ID checking

[qiuwei]

ID checking is defined as part of the Relax NG DTD compatibility specification and being something inherited from DTDs, their definition should be consistent for an element matched by a Relax NG pattern.

However, the rnc is converted automatically from xsd. It doesn't support ID checking.

For further information, check
relaxng/jing-trang#211