This is the latest proposal for adding datatypes for all literals:
http://www.w3.org/2011/rdf-wg/wiki/StringLiterals/LanguageTaggedLiteralDatatypeProposal
It obviously affects Jena because current code was written when plain
literals didn't have datatypes.
Reactions?
Personally, I'm neutral. It's a bit easier if all literal had datatypes
but we're not starting from a blank sheet and the bebefit s small. (I'd
prefer xsd:string to be deprecated and no other changes made.)
At Jena3, we could simply make the change; in Jena 2.X, we don't.
Andy