bug in 5.0: olink xrefstyle

The current 5.0 schema has a bug in the olink xrefstyle attribute, which is
declared as type IDREF.  It should be of type text.

db.olink.xrefstyle.attribute = attribute xrefstyle { xsd:IDREF }

should be:

db.olink.xrefstyle.attribute = attribute xrefstyle { text }

Bob Stayton
Sagehill Enterprises
DocBook Consulting