From SPARQL Working Group
Draft reply to: HSt-1
Thank you for your comment about D-Entailment Regime.
In the current editor's draft, the D-Entailment Regime no longer prescribes a fixed datatype map. Thus, systems that implement the D-Entailment Regime are free to support xsd:hexBinary and xsd:base64Binary.
The current editor's draft is available at: http://www.w3.org/2009/sparql/docs/entailment/xmlspec.xml
Regarding your example query, the answer would indeed be true if the queried endpoint supports the D-Entailment Regime and includes xsd:hexBinary in its datatype map. In this case, the query answers are determined based on the data values and not on the lexical forms and white space does not change the actual data value.
As you suggest, it would also be possible to use SPARQL endpoints that do not support D-entailment, provided that users & applications use only use canonical forms of literals, e.g., without whitespace.
We would be grateful if you would acknowledge that your comment has been answered by sending a reply to this mailing list.
Birte, on behalf of the SPARQL-WG