HTTP PUT of RDF into JPEG

This may be a silly question, but I haven’t been able to locate a definitive answer in the user manual, FAQ, mailing list archives or indeed anywhere else online:

1. I can configure Jigsaw to extract and return only the RDF metadata from a JPEG using a simple HTTP GET command with ;application/xml at the end.
2. My question is: Is it possible to insert only the RDF metadata into a JPEG using a HTTP PUT command, or must we use a filesystem tool such as RDFPic and then afterwards upload the entire JPEG file?

I am very interested in using Jigsaw in a RESTful semi-automatic photo annotation system, but have been unsuccessful to date in this particular endeavour. GETting and PUTting just the RDF metadata from/to online JPEGs would be extremely elegant and RESTful (as well as extremely cool!).

Thank you all very much for reading, and I look forward to hearing back from some of you soon,

Fergal Monaghan,

DERI Galway.