Wikimedia Bugzilla is closed!

Not rigorously tested, but seems to occur only with OGG files.

error 
 code="internal_api_error_MWException" 
 info="Exception Caught: Internal error in ApiFormatXml::recXmlPrint: (streams, ...) has integer keys without _element value. Use ApiResult::setIndexedTagName()."

 <Bryan> it is because the api uses unserialize(img_metadata) directly
 <Bryan> which won't work when you are having lists in combination with the xml printer
 <Bryan> you'll have to use setIndexedTagName or something like that