xerces 2.0.0 DOCTYPE root "null" error

[Bernhard Lenz]

I’m trying to parse the following xml using xerces 2.0.0 with validation and namespaceaware turned on.   <?xml version="1.0"?> <!-- both namespace prefixes are available throughout --> <bk:book xmlns:bk='urn:loc.gov:books'          xmlns:isbn='urn:ISBN:0-395-36341-6'>     <bk:title>Cheaper by the Dozen</bk:title>     <isbn:number>1568491379</isbn:number> </bk:book>   However I’m getting the following error: Document root element "html", must match DOCTYPE root "null".   Does anybody know how to handle this error?   Thanks Bernie