WD-rdfa-in-html-20100624 DTD related issues

Hello,

I noticed a few issues in WD-rdfa-in-html-20100624 while trying to validate a 
tiny document against the DTD.

First, the DTD contains a couple of syntax errors, see two first hunks of the 
attached diff.

Second, the third hunk in the attached diff is there mostly just to highlight 
that the example in section 2.1 "Document Conformance" of the spec does not 
validate against the DTD.  Value of the version attribute in the example 
should either be "-//W3C//DTD HTML 4.01+RDFa 1.1//EN" or the DTD changed to 
match the example (which is what the diff does for illustration purposes).

Third, the public id in the example of appendix B ("-//W3C//DTD HTML+RDFa 
1.1//EN") is not the one mentioned in the DTD, I suppose it should be changed 
to "-//W3C//DTD HTML 4.01+RDFa 1.1//EN" ("DTD HTML 4.01" instead of "DTD 
HTML") in the specification.