+ $xs->element(ActivityContext::CONVERSATION, null, $this->context->conversation);
+ /* Since we use XMLWriter we just use the previously hardcoded prefix for ostatus,
+ otherwise we should use something like this:
+ $xs->elementNS(array(ActivityContext::OSTATUS => 'ostatus'), // namespace
+ 'conversation', // tag (or the element name from ActivityContext::CONVERSATION)
+ null, // attributes
+ $this->context->conversation); // content
+ */