AtomPub applyAcl expects Atom entry response

AbstractAtomPubService.java (line 743):

HttpUtils.Response resp = put(aclUrl, Constants.MEDIATYPE_ACL, new HttpUtils.Output() {
public void write(OutputStream out) throws Exception

{ JaxBHelper.marshal(JaxBHelper.CMIS_OBJECT_FACTORY.createAcl(aclJaxb), out, false); }

});

// parse new entry
return parse(resp.getStream(), AtomEntry.class);

The spec is not clear, but I would expect the PUT response to return a media type of application/cmisacl+xml.