There is a newer Jena 2.x release available (2.13.x). This is a ticket to track updating to that version.
A significant difference with this version is that all String literals now have a defined DatatypeURI. In RDF 1.1, there is no difference between "abc" and "abc"^^<http://www.w3.org/2001/XMLSchema#string>, and this change simply makes that more explicit in the serialization.
2.13.0 also has artifacts built as OSGi bundles.