Should set statusCode to 206 #1
Description
As spec says:
If a syntactically valid byte-range-set includes at least one byte- range-spec whose first-byte-pos is less than the current length of the entity-body, or at least one suffix-byte-range-spec with a non- zero suffix-length, then the byte-range-set is satisfiable. Otherwise, the byte-range-set is unsatisfiable. If the byte-range-set is unsatisfiable, the server SHOULD return a response with a status of 416 (Requested range not satisfiable). Otherwise, the server SHOULD return a response with a status of 206 (Partial Content) containing the satisfiable ranges of the entity-body.
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
As it turned out, there are couple of bizarre caching proxies out there, which does strip the Content-Range header if the status code isnt 206. (like polipo)