If I do a curl request where the Content-Type header is json and Accept header is xml, an attempt to set a new image metadata key results in a 500 error. The metadata is set on the backend and subsequent requests succeed. There should be no 500 error.
curl -X POST -H "Content-Type: application/json" -d '{"metadata":{"pew":"pew"}}' -v -H "Accept: application/xml" -H "X-Auth-Token: ${NOVA_TOKEN}" http://localhost:8774/v1.1/images/3/meta
< HTTP/1.1 500 Internal Server Error
< Content-Length: 222
< Content-Type: application/xml; charset=UTF-8
< Date: Thu, 09 Jun 2011 13:35:06 GMT
<
<cloudServersFault code="500" xmlns="http://docs.rackspacecloud.com/servers/api/v1.0">
<message>
You cannot set Response.body to a unicode object (use Response.unicode_body)
</message>
</cloudServersFault>
